When I opened up a project I have worked on for a view days, everything was messed up. The GUI symbols are facing upwards and the textures & lighting are not displaying correctly. I already reinstalled 4.18 but it didn’t fix anything.
I faced a similar issue when I set my near clip plane to 0 in the project settings. Reset it back to something like 5. For it to take effect, you’ll have to restart the project. Good luck.
I think this is the solution to the problem. I remember setting it to 0. I already deleted the old project but for anyone facing the same problem, this might work. Thank You!