First sweater ever! Kinda confused. Please help!

Hi, I’m knitting my first sweater ever! So far so good but I’m lost at the neck and shoulder shaping. I have 76 sts in stockinette, and I’ve placed markers around the middle 18 sts as the pattern stated. Then it reads:

Neck and shoulder shaping beg at the same time.

Shape neck, next row(RS); work to first neck marker, join a second ball of yarn, bind off center 18 sts, removing second marker, work to end. At each neck edge, bind off 5 sts once, then 7 sts once; and at the same time, on first row of neck shaping shape shoulders as follows:

Shape shoulders, next row(RS); bind off 6 sts at beg of next 4 rows, then 5 sts at beg of following 2 rows.

So confused!! After binding off the center 18 do I then begin working with the previous yarn or keep with the new ball to finish the row? Also am I supposed to work these rows simultaneously? It says they work at the same time? Any help would be greatly appreciated. Right now I feel like I’m at a standstill. Thanks in advance!!

Welcome to KH!
Yes, these rows work at the same time. The first ball of yarn is used for one shoulder and the new ball of yarn for the second shoulder. So start by knitting to the marker, binding off the center 18sts with the new ball of yarn and finishing the row with that same yarn, Turn and work to the bound off sts, drop the yarn, pick up the yarn attached to the first shoulder and bind off 5sts, then work to the end of the row. Turn to the RS row, bind off 6sts at the shoulder, work to the neck edge, drop the yarn and pick up the second ball of yarn, bind off 5 sts and work to the end of the row. Turn to the WS and bind off 6 sts for the shoulder, work to the neck edge. Continue like this binding off at the shoulder and the neck edges until you’ve completed the shaping. I make a drawing showing the numbers of sts to bind off at each edge and then check them off as I do the bind off so that I don’t lose my place.

This is so helpful!! Thank you so much! Can’t wait to get back to work on it.