I like the Olympus camera that I purchased 40+ years ago.

[Major Nikon]

4. Adorama still has 187 choices for B&W film

https://www.adorama.com/l/Photography/Film-and-Darkroom-Equipment/Film/Black-and-White-Film

Mailers are still the best deal for developing. If you want some I guest you stock up now as the 5 packs are significantly cheaper and Adorama has them listed as closeout. The individual mailers are $13 so $5 more each.
https://www.adorama.com/fjsm36p.html

There's still folks on Etsy that will do developing:
https://www.etsy.com/listing/594684535/35mm-black-and-white-film-processing-and

You can also buy the equipment and chemicals to do it yourself. It's not that difficult and all you need is a bathroom or closet you can make completely dark, or use a bag to transfer the film to the developing tank.