Understood.
Like I said before, I'm doing this for my own messing around (kind of like "ha, i made that and it works"). I can run it all locally with an Apache localhost, so that'll keep me safe[r]
Just to elaborate a bit in case it wasn't clear in my OP, take for example the withdraw page on Ice Dice:
https://ice-dice.com/en/account/withdraw. When you fill in the text fields and click "Withdraw", obviously some function (code) is called and executed on their server(s). How do they do that/what is the [example] code?