For a 23” (58-60 cm) head

You can either use a worsted/aran yarn or 2 fingering/sport yarns held together.

Techniques:
Brioche stitch
Garter stitch
Stockinette stitch

Knitting flat AND in the round
K2tog decreases

It’s a good idea to have 7 stitch markers + 1 beginning of round marker for the crown of the hat.