Found a hamster outside in the snow and rain 😩

So this morning my neighbor found a hamster outside that was following her inside. She went around asking who it belongs to. And we’re pretty sure we know who it belongs to and that she just dumped the poor thing outside. I decided I’m going to take it in and care for it. Its teeth look like they weren’t taken care of at all. I’m going to assume it was neglected. It’s been a few years since I’ve had a hamster and I learned a lot from here when I had my last lil guy. Trying to rack my brain on some things I can get right away for him at the local pet stores. We have a petco and petsmart. Do they carry any food or essentials that are okay to put in his tank? I’ll be ordering things for him, just need some essentials for the time being.