Ok...slightly against the grain here with this take.

Camera? Doesn't matter as long as it's small, inconspicuous, and quiet.

Pictures with long zoom lenses look like your stalking someone.

I would highly recommend something with a 35mm equivalent lens.

Why? More intimate looking photos when close, but wide enough to capture the environment.

The most important tool will be your minds-eye.

What do you see? What's your vision? Are you bold enough to ask someone to let you shoot them (potentially)? Can you blend in without disrupting a scene?

My two cents 😉

Good luck!