Help with a pattern needed!

Can anyone help me decipher a pattern? I’ve been knitting for a long time (essentially scarves in garter stitch) but am finally branching out and trying some patterns. I’ve started a jumper but can’t get my head around the patterning. I’ve done the ribbed section for the waist but now I’m hugely confused by the bits in brackets in rows 3 and 7:

1st and 2nd rows: rib
3rd row: k2, p2 *(miss next stitch, knit the stitch after, knit missed stitch and slip both off the needle together) twice, p2, repeat from * until last two stitches, k2.
Rows 4,5,6: rib
Row 7: k2, p2, (put right hand needle behind work and knit into back of second stitch, then into front of 1st stitch, slip both off needle together) twice, p2… etc.

Can anyone advise? Maybe I’ll stick to a simpler pattern next time!

Thanks in advance!

Welcome!
Good for you for venturing into something new. These are left and right twist stitches.
Here’s a video for the first (row 3 type):


and the second (row 5 type):