TestComplete: Unable to see c# option while creating project. Is it actually fully supported?

TestComplete: Unable to see c# option while creating a new project. Also, one of your documentation page says that creating test using c# is not recommended. For my My project c# is must so whats the way forward? Can I assume that TestComplete is not the right fit?

Reference Page: https://support.smartbear.com/testcomplete/docs/reference/language/csscript.html#:~:text=C%23Script%20is%20a%20specific,it%20to%20create%20new%20tests.

It says: C#Script is a legacy language. We do not recommend that you use it to create new tests. Instead, we recommend that you use JavaScript or Python:
Please let me know, how to use full c# language for creating test, reusable functions and custom actions?

Please let me know, how to use full c# language for creating test, reusable functions and custom actions?