First thing I see is that you aren’t using Layers properly.
Layer0 should be your current layer nearly all of the time.
Switch all layers ‘ON’.
It would be a good idea to set up some Scene Tabs with chosen views, at least you can step-back to those when you do something unfortunate !
Also you seem to be working on a ‘backup’ copy - on a MAC a backup file’s name ends with a ~
If you open Model Info> Statistics, do you see lots of things listed.
If not you have somehow deleted much of your model !
But if there are things there, try the next step…
Next, have you deleted some geometry with text associated with it it sometimes zooms off into the edge of the solar-system. Then when you do a zoom extents the model seems to disappear but it’s actually so small you can’t see it !!
Look at this for a ‘fix’…
Need Help to fix my SKP file! - #19 by TIG