are the chess.com lessons worth buying membership for?
If you know very little about chess yes. Eventually like learning to ride a bike and taking off the training wheels you will no longer need them, then cancel.
Have you exhausted all other free instruction options?
library books are free. The USCF has free instructional material. There are scores of free websites that offer instruction. There are many thousands of free instructional videos.
The problem isn’t the site. The problem is that you are not putting in the work needed to benefit from the free material on the site. If you don’t put in the work, then it will not be worth it to pay for more lessons.
If you use it, it's worth it.. if you don't, it isn't. I've used it in the past and found it worthwhile.. currently I hardly play, just easy bot games fairly thoughtlessly... So it wouldn't be worth it for me currently (unless they finally introduced a Tigran Petrosian bot). If you'd make regular use of it, then yea.