i didn’t unsterdand what you mean in your message, so you have the basic knowledge in c# ?
if yes then you have few link who could help you :
https://forum.cfx.re/t/only-c-developing/37772
https://wiki.fivem.net/wiki/Main_Page
https://forum.cfx.re/t/scripting-in-fivem-using-c-where-to-start/7741
good luck