Keeping Fish In A Dorm Room

Hi, this is my first time making a Reddit post but this community seems very helpful and understanding! I searched around but I want to make sure I'm doing the right things.

Context: I currently live in a dorm room and I will do so next year as well, I really hate being all alone and the only pet the dorms allow are fish in less than 10-gallons. Considering there's not a lot of room, I thought a 5-gallon tank would be best for me (although I'm not entirely sure considering I haven't been able to see the dimensions in person). I have not started any processes and I definitely do not own any fish yet.

I would like to start with a single male betta as I've read that they tend to be okay with less room than females.

Any tips to whether this is a feasible plan? I've done a lot of research but I'm also open to any personal tips for a new fish owner!! (Cycling, whether any tank mates at all would be possible in the future, what brands to use, what tank to buy, etc, etx)