Desired set-up:

Light fixture outside front door is on Breaker 1 and controlled by a
single switch inside the front door.

Light fixture over garage door is on Breaker 2 and controlled by two 3-
way switches - one in the garage and one inside the front door.

Can the single switch and a 3 way be installed in the same box even
though they are on different circuits?

Do the breakers have to be ganged if this done?

Thanks!