Aproton and an electron are moving up when they enter a magnetic field that points away from you. what happens to the motion of the particles?

A proton and an electron moving up together in an magnetic field will eventually converge. The proton is attracted to the electron as well as the other way around. One way or another, as they move up, the difference in the charges causes their motion to be moving towards each other making them cross their path in hope for stability or neutrality.

That would be kinetic energy

Hypothesis. why don’t you know this? i learned this stuff in like 5th grade