Crochet help with pattern


My question is, I am making a small, cast off mid front for neck. So I’m starting my next row, I’m crocheting along and then I cast off 2 sts during that row. twice, then 1 st during the next 5 rows? Before I start this I have 41 sts so I was going to cast off at st 20 and 21 now I have 39 cast off 1 st at 18 and so on? At the same time I will be casting off or my arm hole.

Am I thinking right?

This is from Drops kintting pattern # 99-11

Thank you for your help in advance

when piece measures 30-31-32-33 cm cast off for neckline. (If neckline should not be deep, wait with dec for 3-3-4-4 cm).
Size S and M: Cast off on each row.
Size L and XL: Cast off on every other row.
Cast off 12-12-13-13 sts mid front for neck, then cast off to shape neckline 2 sts 2 times and 1 st 5 times. At the same time when piece measures 32-33-34-35 cm cast off for armhole like back piece. After completing all cast offs for armhole and neck 14-15-16-17 sts are left on shoulder. Cut thread when piece measures 50-52-54-56 cm.

You are making one side of the front and then will make another mirror image of that one. When you have it the length you want it up to the neck opening you want to cast off 12 on the side that will be the neck side. If it is at the beg of the row you sl stitch over 12, if it falls at the end of the row you stop 12 before you get to the end (thereby casting them off). Then because it is a small you will get rid of stitches on each row. First you get rid of 2 stitches on the next 2 rows. Again I’m not sure where these fall, at the beg or end of the row but if it is at the beg you slip stitch over the first 2 stitches and if it is at the end you stop short without working the last 2. You do that for two rows, then you get rid of 1 st 5 times doing it the same way slip stitching across it if it is at the beg of the row and stopping before you do the last stitch if it falls at the end of the row. While you are doing that neck shaping begin the armhole shaping for the front when the piece is 32cm long working it like you did on the back. When you’ve finished all the armhole and neck shaping you will have 14 stitches left. Work to 50cm and end that side.