Good US cities which are social and drivable? Want to base myself there for 2 weeks.

This isn’t strictly road trip-related, so I understand if it gets removed, but I’ll give it a shot.

I’m solo travelling across Asia and North America for a few months starting in May.

When I’m in the US, I want to base myself in one city for two weeks. Here’s what I’m looking for: 1. A place where I can focus on fitness. Nothing fancy, I just want daily access to a gym and to stay on top of my protein intake daily. 2. A social city where it’s easy to meet people quickly. I’m social, and solo travel already pushes me out of my comfort zone. I worry that mega cities like New York might feel too anonymous. Maybe San Francisco too. I realise this might be a tall order, but in parts of Asia, locals often treat tourists like a novelty, which makes it easier to make friends fast. Is that kind of experience possible in the US? 3. Good nightlife. I’m into clubs, bars, live music. Doesn’t need to be all of these (I know not all cities in the US have decent club scenes) but any of it. 4. A drivable city would be a bonus since I’ll have a car with me.

For reference, im in my late 20s from the UK.

Would love your tips!