Kayaking without knowing how to swim

Hey guys, i am pretty excited about kayaking, and was thinking of going to a guided tour for 3 hours at kayaking with Salty dogs, but they said for kayaking knowing how to swim is a must, do we need to know swimming for kayaking?

Edit: thanks for the replies, everyone! Skipping kayaking for this trip, extremely scared to get my kayak capsized in the ocean.