How do stars and planets orbit a black hole without being destroyed by it
This is a common misconception about black holes. Black holes do not have any more gravity than any other body of the same mass!
To explain, suppose our sun suddenly collapsed to become a black hole (this is actually impossible, because you'd need a mass about 3 times that of our sun to collapse all the way to a black hole). But let's pretend it happened.
What would happen to the earth and the other planets? Would they be sucked in? No - they would continue in their orbits! They would feel the same gravity from the sun, whether it was a black hole or not.
Where things start to get sucked into the black hole is when they get close to the "event horizon". For a mass of the sun, the event horizon has a radius of about 3 km. Earth is (on average) about 150 million km from the centre of the sun - a LOT farther than 3 km! So earth will experience no great effects.
If a comet approached the black hole sun and got approximately 3 km from the centre of the sun, then it could very well be sucked in and never heard from again.
So remember - black holes are only "dangerous" if you get very close to their event horizon (which is usually small for stellar black holes).
Hope that helps,
Prof. James Gort