Longtime users of Linux have all kinds of tricks up their sleeve
to make their work more efficient. Rather than you figuring all of
that out on your own, here's all their deepest guarded tips, for free:
Quick Reference Guide
Alt Tab: Switch between applications
Alt `: Switch between windows in one application
Windows or Apple key: Go to your Activities Overview
Control f: Find files on your computer
Control q: Quit an application, closing all of its windows
Control w: Close the current window
Control c: Copy text, or a file
Control v: Paste text, or a file
Activities Overview > Add/Remove Software: Find and
install new software
Activities Overview > Applications: Find and
launch software already on your system
Activities Overview > Files: View your files on your computer