I understand your budget is 10K. I had this same conundrum a few years ago with 12 and 14 year old. Buy something she can use for at least 5 years. This is what I did and I have no regrets. You might spend a bit more now, but she will be better off. Please don't buy online. Go to a shop. Look around. Don't let them install their junk W10 orW11 when the computer comes with it. I think we spent 15K each.
BTW I am not a computer expert. This is my opinion based on having girls about the same age, and what they use the computers for.
Watched old guys wander around Central like they were completely lost. Immigration too. Then. got on an Mbike. Crazy