Thinking of getting a puppy

Hi guys, I recently graduated high school and am going to start university in around two months. I’ve been wanting a puppy for the longest time and figured now would be a good time to consider getting one since I’ll have lots of time to really buckle down and work on training and socialising it before I start school. The only problem is, I’m planning on getting a part time job during this break as well so I’m worried about leaving the puppy at home for a couple of hours at a time. I do live with my mum, but she goes to work a couple days of the week as well so there might be times when no one is home to take care of the puppy. I know getting an older dog is an option and while I’d love to (I actually might prefer it), we have a cat already and I think it would be ideal if the dog/puppy has grown up with a cat to hopefully reduce the chances of the dog harming my cat in the early stages… Or, if anyone has had success introducing an older dog to an existing cat and them getting along I’d love to hear about it! I also live quite close to my uni (around a 15 min drive) so the max amount of time the puppy might have to be alone would be around 3 hours once uni starts, but realistically it might be longer depending on my schedule. Would it be a good idea for me to get a puppy right now?