This should be your starting point whenever you have a question or uncertainty.
This post connects other basic contributions and provides an overview.
Find out everything that will help you create your first gamemode in C#.
Good to know examples and tips
What is available in C#?
The early beginnings of bug hunting
What is restricted or forbidden?
The file system of the player
Libraries and API calls
All beginnings are difficult - Wrong! After you have successfully created a project, you need the necessary knowledge to get started. API documentation and possible suggestions