4 DOUBLE CROCHET into ONE STITCH. Look- the pattern has you make nine chains, or “9 sc” sc being single crochets. So, you’ve got a chain with nine stitches on it. Don’t put a stitch into the first one, start on the second st (it would be physically impossible to put a st into the 1st one anyway, & fiddly to even place one in the 2nd as instructed) – then you just put a double crochet into EACH ST til the last one, which you stitch FOUR DOUBLE CROCHETS into that last stitch- giving you 22 sts! It went from 9 sts, up to 22. Those double crochets/DC’s gave you increases.
On a crochet forum yrs ago, someone wrote something that was a life-saver: "Don’t worry, there are no ‘crochet police’ to come arrest you for doing it wrong’ something to that effect. So, go ahead and learn your stitches, look at the pattern and count your stitches on each row- compare it to what the pattern says. Now, a caveat, sometimes patterns can be wrong! So, simple multiplication will sort it out.
Whenever I got confused, or mixed up in a pattern and was not sure where to turn, I would go ahead and do it as I thought it was supposed to go- knowing there were no “crochet police” over my shoulder, many times it came out alright, I just followed the instructions, not fussing over whether it “seemed right” or not.