プロキシを通したライブラリ（PyAutoGUI）のインストール

前提・実現したいこと

Pythonを勉強し始めて1か月程度の初心者です。他にプログラミング経験はありません。
PyAutoGUIライブラリをコマンドプロンプトにてインストールしようとしているのですが、うまくいきません。
会社でプロキシがあるので、プロキシがある状態でのインストール方法を調べて試しましたができず、
オフラインでもインストールしてみましたができませんでした。
エラー等を見る限りPyAutoGUIをインストールする場合はオンラインが必要な感じがします。
どうしたらインストールできますか？
プロキシのセットや書き方が何か間違っているのでしょうか？

ご教示よろしくお願いいたします。

発生している問題・エラーメッセージ

⓵
C:\Users\******>py -m pip install pyautogui --proxy http://[ID]:[PASS]@proxy2.*********:8080
Collecting pyautogui
  WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))': /simple/pyautogui/
  WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))': /simple/pyautogui/
  WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))': /simple/pyautogui/
  WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))': /simple/pyautogui/
  WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))': /simple/pyautogui/
  Could not fetch URL https://pypi.org/simple/pyautogui/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pyautogui/ (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))) - skipping
  ERROR: Could not find a version that satisfies the requirement pyautogui (from versions: none)
ERROR: No matching distribution found for pyautogui
Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pip/ (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))) - skippingSSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: self signed certificate in certificate chain (_ssl.c:1108)'))) - skipping

⓶
C:\Users\******>set HTTP_PROXY=http://[ID]:[PASS]@proxy2.*********:8080

C:\Users\******>py -m pip install pyautogui
Collecting pyautogui
  WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x042E98B0>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui/
  WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x042E99D0>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui/
  WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x042E9B80>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui/
  WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x042E9328>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui/
  WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x0432A040>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui/
  ERROR: Could not find a version that satisfies the requirement pyautogui (from versions: none)
ERROR: No matching distribution found for pyautogui

⓷
C:\Users\******>cd Documents

C:\Users\******\Documents>py -m pip install --no-index --find-links=pyautogui_src pyautogui
Looking in links: pyautogui_src
Collecting pyautogui
Collecting pymsgbox (from pyautogui)
  Installing build dependencies ... error
  ERROR: Command errored out with exit status 1:
   command: 'C:\Users\******\AppData\Local\Programs\Python\Python38-32\python.exe' 'C:\Users\******\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip' install --ignore-installed --no-user --prefix 'C:\Users\******\AppData\Local\Temp\pip-build-env-sxmby76v\overlay' --no-warn-script-location --no-binary :none: --only-binary :none: --no-index --find-links pyautogui_src -- 'setuptools>=40.8.0' wheel
       cwd: None
  Complete output (4 lines):
  Looking in links: pyautogui_src
  Collecting setuptools>=40.8.0
    ERROR: Could not find a version that satisfies the requirement setuptools>=40.8.0 (from versions: none)
  ERROR: No matching distribution found for setuptools>=40.8.0
  ----------------------------------------
ERROR: Command errored out with exit status 1: 'C:\Users\******\AppData\Local\Programs\Python\Python38-32\python.exe' 'C:\Users\******\AppData\Local\Programs\Python\Python38-32\lib\site-packages\pip' install --ignore-installed --no-user --prefix 'C:\Users\******\AppData\Local\Temp\pip-build-env-sxmby76v\overlay' --no-warn-script-location --no-binary :none: --only-binary :none: --no-index --find-links pyautogui_src -- 'setuptools>=40.8.0' wheel Check the logs for full command output.

⓸
C:\Users\******\Documents>py -m pip install pyautogui_src
Collecting pyautogui_src
  WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x04429838>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui-src/
  WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x04429460>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui-src/
  WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x04429B98>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui-src/
  WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x04429628>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui-src/
  WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'NewConnectionError('<pip._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x04429AA8>: Failed to establish a new connection: [Errno 11002] getaddrinfo failed')': /simple/pyautogui-src/
  ERROR: Could not find a version that satisfies the requirement pyautogui_src (from versions: none)
ERROR: No matching distribution found for pyautogui_src

⓹
C:\Users\******>cd Documents\pyautogui_src

C:\Users\******\Documents\pyautogui_src>py -m pip install PyAutoGUI-0.9.50.tar.gz
Processing c:\users\******\documents\pyautogui_src\pyautogui-0.9.50.tar.gz
Collecting pymsgbox (from PyAutoGUI==0.9.50)
  WARNING: --------字数制限の為短縮　⓸と同一エラー繰り返し--------
  ERROR: Could not find a version that satisfies the requirement pymsgbox (from PyAutoGUI==0.9.50) (from versions: none)
ERROR: No matching distribution found for pymsgbox (from PyAutoGUI==0.9.50)

該当のソースコード

⓵
py -m pip install pyautogui --proxy http://[ID]:[PASS]@proxy2.*********:8080

⓶
set HTTP_PROXY=http://[ID]:[PASS]@proxy2.*********:8080
py -m pip install pyautogui

⓷
C:\Users\******>cd Documents
C:\Users\******\Documents>py -m pip install --no-index --find-links=pyautogui_src pyautogui

⓸
C:\Users\******\Documents>py -m pip install pyautogui_src

⓹
C:\Users\******>cd Documents\pyautogui_src
C:\Users\******\Documents\pyautogui_src>py -m pip install PyAutoGUI-0.9.50.tar.gz

試したこと

以上のようにいろいろ試していますがインストールできておりません。
プロキシはPACを開いて一番下の行にあった複数（proxy2,3,4）を試しましたができませんでした。
⓷～⓹のように、オフラインでインストールしてもエラーが出ます。
パッケージの中を１つ１つオフラインでインストールした場合（⓹）、
PyAutoGUIとPyMsgBoxだけインストールできませんでした。

補足情報（FW/ツールのバージョンなど）

Python 3.8.2 (tags/v3.8.2:7b3ab59, Feb 25 2020, 22:45:29) [MSC v.1916 32 bit (Intel)] on win32

Package     Version
----------- -------
et-xmlfile  1.0.1
jdcal       1.4.1
MouseInfo   0.1.3
openpyxl    3.0.3
Pillow      7.1.2
pip         19.2.3
PyGetWindow 0.0.8
pyperclip   1.8.0
PyRect      0.1.4
PyScreeze   0.1.26
PyTweening  1.0.3
selenium    3.141.0
setuptools  41.2.0
urllib3     1.25.9

今までインストールした物はとりあえずオフラインで入れています。