Hat question Please help

the pattern says to cast on 90… no problem
then it says to join in round rib 2 x 2 for 1 inch
then switch to stockinette and work for 5 rows.
Decreasing 2 sts evenly spaced in row 88 sts.

Can someone explain it easier.

If it’s “rib 2x2” that’s throwing you off, they mean "work k2, p2 around for one inch."
Five rows of stockinette in the round=knit five rounds.
Decrease two= the easiest way would be to knit the first and second stitch together and knit two together about halfway around. 88 stitches left will most likely be a certain number of pattern repeats.

It’s odd that they ask you to cast on 90sts however for k2p2 rib since 90 isn’t a multiple of 4. You would end up with 4 knit sts at the join to work in the round, unless that’s part of the pattern.
You could cast on 88sts to begin with and continue with the directions, leaving out the dec of 2sts since you already have 88sts.

Can you give us a link to the pattern or a pattern name?

Welcome to KH!