Question about the editor

I was thinking about what things can you use inside a game and witch one you cant …i mean can you use the terrain tools you use in the editor inside your game ? If not how you distinguish something that can be use and something that cannot be use …or i sould said access ?

maybe im expressing myself wrongly i hope you understand what i mean

Basically, if it has “Editor” or “Tool” in it’s title, it’s part of the editor and not part of the final “Packaged” project. Things like Terrain and Foliage tools are part of the editor.