Confused on terminology

I’m knitting a Vogue pattern # 18 Drop Collar Cardi and after finally finding and using the errata for this pattern have been able to make a little progress. My question is : if it says bind off 2 sts, do I do so individually or bind off 2 together?
Also, how do you cast on stitches over bound-off stitches? Add another piece of yarn?

Hello
It is not likely to be 2 bound off together. It is more likely bind off 1 then bind off another 1.

The cast on, is this on the next row when coming back across? You don’t need extra yarn you use your working yarn which is attached to your stitches. Just get to the right place in the row and do a knit cast on, or 2 or however many it says. Then continue knitting or purling as your pattern says, same yarn.
My guess is this is a button hole but I could be wrong.

Yes , a buttonhole. Thanks for the tips!

Same pattern, now at the first increase row (RS):
Work 22 sts front rib panel, [work to 1 st before marker, yo, k1, Sl m, k1, yo] 4 times, work to end. Working inc sts into seed st, rep inc row every 4th row 1 time, ( I think this means:
inc RS
WS
RS
WS
Inc RS
Am I correct in that pattern?
after the , comma it says: every other row 18 times.
I started this pattern with 92 stitches on my needle and after the first inc row RS I have 100 stitches. Increasing 19 more times ( every other row) doesn’t get me to 252 stitches. What am I missing?