Inside Roblox Studio, place a new MeshPart into the world by clicking the Plus symbol next to Workspace. Type “mesh” in the search box. You should see MeshPart in the list of available objects.

For example, you can import a sports car into Roblox Studio without spending a cent. For more Roblox tips, check out Roblox's own walkthroughs and my books on how to script games.