They eat fresh squid, shrimp, and flounder. You can also train them to eat frozen shark formula.
Feed it every other day until it is full.
The longest time you could keep one in a 72 would be about 6 months. Since it is about 7-8 inches now, after 6 months it will outgrow your tank.
They are not catsharks. They are bamboo sharks. Catsharks are entirely different. Sorry, this is a pet peeve of mine.
You can expect it to reach a size of just over 3 feet and the bands will disapear with age.
What other fish do you have? They could either kill the shark or become food for the shark.
Don't buy the banded unless you can dedicate a tank much larger than a 72 for it.