This is probably in the manual somewhere, but...

The keyboard has shift and control keys and they do what you would expect with selections. Control-tap adds, Shift-tap selects a range.

Also Control-C/X/V will do copy/cut/paste.

And there are shortcuts like control-q for close which appear in the menus.

If you have an external (e.g. bluetooth) keyboard Alt-Tab brings up the app switch, and there are many other shortcuts or things that work just like a typicall Linux (or mac/win) install.