yes, FM is a good camera, a fully mechanical camera, also fully manual operating camera.
to learn about film photography, all you need is a film camera in working condition which has manual exposure mode, many film cameras can do that, not limited to FM only.
You don't have to, it is so simple to use it, have only one ISO dial, one shutter speed dial, one aperture ring, and one focusing ring, and have one and only exposure mode, how to compare to a modern DSLR have so many bottoms, dials and so many mode and functions?
btw, FM is my 1st camera which I bought with my own money.
The FM2 is the camera that many now-world-reknown pros learned to shoot with. It was popular because it had advanced features (1/4000 shutter speed for one) packed into a compact and very durable body that was priced for consumers. It was the first of it's kind.
If you want to start from film, then the FM2 is a pretty good deal for 'forcing' you to learn about exposure and such, because it doesn't have an automatic mode. If you want an automatic mode, or at least aperture/shutter priority, then another camera like the N80/F80 might be a better choice. Note though that most cameras with automatic/Av/Tv aren't built as well as the FM2, using plastic bodies instead of metal.
For myself, I found digital to be a much easier learning process. I don't have to worry about film and it's costs when I snap, and I get the ability to instantly see if my composition or exposure decisions were good or bad.