I'm going to be honest as shit with you. Non I that cute backpack stuff is going to matter a month into school when the strap breaks because it wasn't meant to hold a textbook. So get something substantial. I recommend a jansport because they're cheap but sturdy and come with a lifetime warranty
A Jansport would be your best bet. They make many with different prints or cool solid colors, and different sizes for your needs. They should have some for less than $50 for sure. I'm not sure how fashionable you're talking, ha, but they're good bags!