"The project file or web cannot be found"


I was learning to program in Unreal and I encountered a problem: "FMeshDrawSingleShaderBindings" is undefined - UE4 AnswerHub I did what the top answer said but now I’m getting an error in Visual Studio saying “The project file or web cannot be found”. I attached a screenshot of how it looks. I’ve tried rebuilding Visual Studio files but that didn’t help. Any way to fix this?

I have also recently started having this problem after deleting the “Binaries”, “DerivedDataCache”, “Intermediate”, and “Saved” folders, even though I had done this many times before after pulling from my Github repository. It’s causing me to be unable to use Intellisense or tell if there are errors in my code which in turn is causing me to lose a massive amount of time debugging and recompiling trying to find the issues. Please help!