How to decrease while staying in pattern

I’m doing a k1p1 ribbing pattern, but I am suppose to decrease twice. Once by a k2tog and once by ssk. How do I do this while staying in pattern?

You really can’t. The decrease is going to change the pattern. Go ahead and do the decreases. Depending on the next row, maintain the k1p1 pattern until you get to the area of the decrease and then follow the stitch pattern from the previous row.
Where are you in the pattern? Are you changing from rib to another stitch pattern?