Hey, @
shadowMaker3697 and welcome!
If possible, you can join the Discord if you need some more direct and quick response to some of your questions here!
Regarding the vs2015 offline installer, you don’t need visual studio per se, but it’s certainly the easiest way to compile the engine.
You can use a newer version if you get your hands on it, doesn’t have to be 2015 version.
However if you don’t need to modify the source code, you can go pre-built binaries and scripting instead as well! It’s a much quicker way to get started with T3D.