Solar orbits aren’t something you want to mess with even if you could. Move Earth a little and it could cause other planets to shift, eventually throwing the whole system out of whack and ejecting planets into space or bombarding us with comets from the kuiper belt.

You could accomplish cooling with volcanic eruptions, but this usually blots out the sun and makes growing crops a real issue.

Moving the world away from the sun? Not even close to possible today. Make the atmosphere dark or reflective enough to cool? Yes, but more ice would be bad for crops.

The rise of humanity came out of the end of the last ice age. So I think heat is good, we just need the right balance.