I have Charter Cable internet in one room and I have a laptop in another.

I need to connect my laptop that has wireless internet built in to my aunts cable internet. my sister said that I could get a router but I don’t know what kind to get? I have a wireless USB network adapter that I connected my desktop to with wireless in college but since I have a laptop I dont know if that is even in the equation. Does someone know what Router I need? The two computers are in different rooms.