I was also late to get into skin care. I don’t think my DM has used a moisturiser in her entire life, let alone a serum or any kind of anti/ aging product.
My DDs are much older teens, have simple skin care routines and use minimal make up. They tease me about my stash and are pretty unfussed about brands. For a couple of years when she was around 12/13 DD1 had the Soap and Glory calendar, which I did think was appropriate at the time - bath and body stuff as well as skincare, which she enjoyed.
On the plus side, the bit of make up DD1 does do is usually the flicky eye thing, so black eyeliners don’t go to waste in our house.