Honestly, as someone whos seen plenty of tablets get trashed in backpacks, I would suggest being really careful with your choice here. Since youre starting a design course, you might want to consider that most $20 knockoff pens dont have pressure sensitivity. Sketching without that is gonna be a total nightmare for your assignments, basically like drawing with a mouse. I think the safest play for your $70 budget is to split the difference so you dont end up with broken gear or a dead battery by midterm:

• Look for a Logitech Crayon for iPad Digital Pencil. Its usually around $50 and its much more reliable than the no-name brands you find online. It doesnt have pressure sensitivity, but the build quality is way better for daily heavy note taking.
• Grab a basic but sturdy case like the ESR Rebound Magnetic Case for iPad Pro 11-inch. Itll keep the front and back safe from scratches for about $15 to $20.
• If you have any change left, make sure to get a amFilm Tempered Glass Screen Protector for iPad Pro 11-inch. A screen repair will cost way more than your whole budget. I would stay away from those thrift store sleeves for now... they dont really offer any drop protection if you bump your bag on the bus. Just be careful with the cheap knockoff styluses because they often disconnect or the tips wear down instantly. If you can find a used Apple Pencil 2nd Generation Wireless Charging locally today for $70, that would be the best move for a design student, but definitely prioritize reliability over a fancy case right now. Let me know if you need help finding where to grab these fast.