Help me buy a PC for online class

Hello, my name is Sophia! I'm planning to build a pc for me and my brother's online classes that would also last until I reach college. (Currently in 9th Grade 😊) I've been using my phone for all my academics but unfortunately, it's been getting slower, I don't want to bug my parents to buy me a new one since I know they're working hard to feed us. Right now I'm really interested in the field of Information Technology and having a powerful pc would benefit us a lot.