So I just recently began learning how to script and I don't have a lot of knowledge on this subject but I was wondering how to upload a mesh. At first, I opted on watching videos on how to upload one into Roblox Studio. I understood most of it, but what really confused me was the whole FBX file thing. I have no idea how it works! None of the tutorials I watched fully explained what or how to use an FBX file. Please send help. >~<
roblox only supports meshes encoded either in FBX or .OBJ with a limit of 10K triangles. Meshes themselfes can only be created in a modeling program which will allow you to encode them in some sort of file type.
If you want to make meshes search for: "Blender", its a free app which is extremly good for modeling. If the question is on how to add it into the map once you have the mesh file on your computer: In Studio, go to "view" and open the "game explorer" tab; in it right click the meshes folder and click "add asset".
Hope this helped
Export the file in your 3D editor as an FBX or .OBJ file, then in Roblox Studio, open up the Explorer tab, and Properties tab. From there, add a mesh to Workspace in the Explorer tab. Find the Mesh ID or FILE, and click on that and then locate where your mesh is on your computer.