I’m not sure what you want, but you have to be very careful with what keys you press, because many are hotkeys and you might end up doing things you don’t want.
For instance you are at the last frame of the animation (Frame 250) and I bet you didn’t do that on purpose;)
So, are you aware that you are in Local View? Numpad / toggles Local View on and off, or go to View > Local View > Toggle Local View.
If something is missing in Edit Mode, maybe you hid it with H. Alt H un-hides (shows) everything….
