Arduino, multiple motors, and multiple batteries

Hey guys! I'm a super new user and this is my first time posting on this forum but I've got a question...

For an upcoming engineering project I've decided to use the Arduino with the adafruit motor shield v2. I need to try and run 3 DC motors off this and I can only use 9V or less batteries (any number of them).

I've read 9V batteries don't run motors well and the adafruit shield instructions say to not even try so I'm wondering what you all suggest? Should I ditch the motorshield? What batteries should I use? How many?

Thank you!

No, you are approaching things backwards.

What are you wanting to power?

You may want to use 9V batteries, but that may be completely pointless, so tell us what
you are actually trying to do, not your proposed solution (xyproblem).