formタグを利用しhttpリクエストを行いたい

以下サンプルコード(Example HTTP Request の下のcodeで囲われたもの)を使用し、credraxへのhttpリクエストをしたいです。
htmlを使用し、

<form method="post" action ="">
<input type="hidden" name ="" value ="">
</form>

といった方法で行いたいのですが、以下の仕様を参照しどのようにやれば良いのでしょうか??

どうかご教授お願いいたします。

Introduction
Transaction requests are sent online, in real-time, using HTTPS (Hypertext Transfer Protocol Secure).
The gateway protocol exposes multiple operation types, including sale (authorisation and capture),
authorisations, reversals, refunds and past transaction retrieval.
Addresses
Integration address:
• https://intconsole.credorax.com/intenv/service/gateway
Production address:
• https://xts.gate.credorax.net/crax_gate/service/gateway
HTTP Specification
• Protocol: https
• Method: POST
• Content-Type: [application/www-form-urlencoded] or [application/x-www-form-urlencoded]
Example HTTP Request

POST /intenv/service/gateway HTTP/1.1
Host: intconsole.credorax.com
Content-Type: application/x-www-form-urlencoded
Content-Length: 176
M=8632876&K=9823ou1pwieufdp91873p98723rp987238r97p198r&O=1&a1=7894654&a4=1099&b1=45
454545454054545&b2=1&b3=08&
b4=11&b5=003&c1=John+Smith&c3=johnsmith@yahoo.com&d1=111.222.0.101

Security/Authentication
All HTTP requests must be sent over SSL, a secure channel should be used. The Credorax Payment

Gateway does not authenticate the SSL session using a certificate from the client, thus a non-
authenticated SSL session is used. Instead the client is first authenticated using source IP plus a

secondary authentication check using an MD5 message cipher which is sent in the request payload and
used to verify before processing. See Appendix A: Message Cipher for further details.
Note: Starting February 2018, new merchants should use SHA256 hashing instead of MD5 hashing. For
more information, see SHA256 Hashing in Appendix A: Message Cipher.