One of the 3 most basic crochet stitches that you must learn is the double crochet. This is a stitch that you will use time after time.
20 Free Christmas Crochet Blanket Patterns (Easy + Festive) - Handy Little Me
How to Double Crochet - Crochet Stitch Tutorial - OkieGirlBling'n
Okie Girl Bling'n'Things (@okiegirlblingnthings)
OkieGirlBling'n'Things
7 Fun & Free Fall Crochet Square Patterns - This is Crochet
Crochet Stitch Tutorial Archives - OkieGirlBling'n'Things
I also have a slower, more in depth tutorial for the joining method on
How to Double Crochet - Crochet Stitch Tutorial - OkieGirlBling'n'Things
Tunisian Crochet Brioche Stitch Tutorial Crochet stitches for beginners, Tunisian crochet, Brioche stitch
20 Heart Crochet Patterns (Free Amigurumi Ideas) - Handy Little Me
How to Foundation Half Double Crochet
Puff Stitch - Crochet Stitch Tutorial - OkieGirlBling'n'Things
Bobble Stitch - Crochet Stitch Tutorial - OkieGirlBling'n'Things
OkieGirlBling'n'Things