Hey there, if you want to create a 2d game on Roblox, you could take a look at this engine: 2D Game Engine | Upside Engine - Resources / Community Resources - Developer Forum | Roblox! I haven’t personally tested it but it seems great. However, if you don’t want a flat camera, you could set the camera FOV to 0 or use an Isometric perspective such as shown here: Isometric Camera View - Resources / Community Tutorials - Developer Forum | Roblox.
Hope that helped!