I think there’s a bug with UE 5s regarding implicit source compilation - i.e clicking the .uproject without compiling via VS first.
UE 4 will pop a window showing progress of compilation but UE 5 does the compilation silently which makes one think that there has been a problem and clicking the .uproject file once again which will pop an error such as this one.
First click right button on .project than “switch unreal engine version” to 5.3
This would generate new files and an .sln
Than hit .uproject again, hold until something pops, do not hit again.
If this window popped - hit the .sln file and Build it (Ctrl + B or Ctrl + Shift + B) - post errors here.