BPM - means Beats per Minute.
That's the number often seen at the start of the music.
Directions: Use a metronome you have at home, by going to https://www.imusic-school.com/en/tools/online-metronome/ or downlad one to a mobile device and try the following exercises.
Start at a very slow tempo (lower numbers) and each time you play the section well and without stopping increase the speed by one or two notches or number until you can no longer play it well.
What was the tempo number you started at? What was the tempo number you stopped at? High five if they were different.
2. Challenge yourself by repeating that activity a couple days or a week later. Do your results change?
What was the tempo number you started at? What was the tempo number you stopped at? Was your second number higher?
3. On many metronomes there are tempo markings (ie. Largo, andante), can you find them on the metronome you are using? Can you play a scale or a music excerpt at three different Tempo Markings?
4. Super Challenge. Set your metronome to 60. With your mouthpiece or instrument see how many beats you can play a note for while making a good sound. What are some of the things you have to do to keep the sound nice and full? Try it with other notes as well.