How to make Backdoor for a server?

[Snarledbear10]

Hey, I'm really new to hacking Gmod but I found a tutorial on here that gave me a bypass.lua, and external.dll, I also found an Odium menu on here but can't use it unless there is a backdoor to a server, so I'm wondering, how can I make a backdoor? I don't know if this is legit but I found this tutorial online, if its true than could someone please explain it to me, if not can someone teach me how to make a real one?

Video I found:

Thanks!

[svyanov]

Learn LUA, PHP and html,css,js for web panel design

Backdoor Example (Simple way & With Server-to-Web connection):
https://www.mpgh.net/forum/showthrea...1#post14863681