Knitting a hoodie sweater

I am a novice in knitting. I have been working on a sweater pattern out of Debbie McCombie’s pattern book “The Good Yarn”. However, I am stumped by an instruction. After having 14" of the pattern it instructs you in joining row to add on 4 additional stitches to the 23 cast on and then pick up 23 additional stitches. My question is do you bind off first but if you don’t how do you pick up the stitches and then knit. Hope I am not being too confusing. If anyone can help please let me know.

You would cast on the 4 sts with your working yarn - use a knit or cable cast on - then continue on picking up the stitches. Don’t bind off.