Hey there @Rk_Russel! Welcome to the community! So it looks like some actors in your level may have been corrupted, though let’s try a couple things and if it helps we might be able to save them.
First step, back up your project.
Try swapping back down to DX11 (this will disable the nanite meshes but show their fallback for the moment), does this allow you to load the map without crashing?
Close the project, delete both saved and intermediate folders and regenerate them by opening the project.