Most 13 year olds go to bed at 9:00 PM but some 13 year olds go to bed as late as 10:00 PM to 10:30 PM.
On average a 13 year old needs between 9 to 12 hours of sleep.
As long as the 13 year old is getting at least 9 hours of sleep then they will be fine.
I used to go to bed at 8:00 PM at age 11 and by age 13 I started staying up until around 10:30 PM
Some nights I would also stay up later and sometimes until midnight but then I would be so tired the next morning and the next day when I had school.
I loved staying up late but hated being tired the next day and would sometimes fall asleep in school.