Here are some how-to guides and patterns that will get you started.
Beginner’s guide — links to stitch instructions, abbreviations, following patterns, seaming, etc.
Basic shapes — squares, granny squares, joined-row circles, in-the-round circles, etc.
Patterns — hats, Harry Potter scarves, Harry Potter afghan charts, etc.
Stitch variations — different or unusual crochet stitches
Navajo 3-ply technique — triple up your yarn without tangles or multiple balls
No-sew ends — keeping ends to a minimum
No chain starting double crochet — a better way to start dc rows than ch3!