Moises is a good place to start. It's got a bunch of features like AI instrument separation, a smart metronome and real-time chord detection. That's particularly useful for drummers and guitarists, letting you practice at your own tempo and in any key, which can be particularly useful for improving.
Another good tool is Drumloop AI, which generates original drum loops based on your input. The tool includes an interactive beat sequencer, so pros and beginners can easily create and customize drum patterns. The loops are royalty free and can be easily imported into digital audio workstations, so you can add some new dimension and energy to your music.
If you're in the transcribing camp, Frettable has powerful AI that can turn recordings of instruments into sheet music and MIDI files. That means you can focus on playing the music instead of typing it out, and it's got features like cloud storage and collaboration tools that are good for musicians of all levels.