Imported large fbx file format model from SketchUP

Hello My PC updated my UE 5.2 after I opened a FBX file 4GB
a large SketchUP model
I had chosen the option to show both faces as at my first attemp many of my faces were missing.
Now when i restarted UE I simply see nothing at all
I took me many month of searching and reading that this may be the issue
and therefor I exported the fbx with that option.
I imported to a blank game mode
I can’t eve figure out what to do next?
For a start I just want to see if my model displays better


This was the stage I had started with that was missing so many parts
It’s a model 9 levels up and 7 levels underground (not all built up)
much open space in betwen its like a city indoor playpark
I have watched the 5 hrs UE tutorial several times
but they don’t tell the simplest thing
how simply SEE your imported file and what to do if it does not open
I followed the instructions "Missing project Settings D3D1`2 and checked
SM5 SM6 and ES3.1 although I don’t know at all what they mean
So many buttons in UE just dont’ tell you what they are for or what they mean
just an observation as a beginner.
Thank you for your precious time of hopfully problem solving advice
Vic