And if you want a pretty good introduction to backup and restore, look on YouTube for ScaryDBA - Grant Fritchey has a video on doing just backups (differential, full, TLog) and various types of restores (full, point in time, etc). Definitely something you should know how to do (and practice!) before you make a hideous mistake on one of your own databases and find you can't undo it...
Here's his YouTube channel: