Getting a non feeder is never a good idea if you have a limited experience with Ball Python they can be tricky to get started which is why it is always highly recommended to get a well started CB from a breeder.

Now the question is ask a lot so we might be able to put you on the right track this is what I would recommend

The main issues with young animals is security, breeder usually keep their animals in VERY small tubs, I keep all my hatchling until they are about 250 grams in a 6 quarts tub.

Some of the keys with hatchling is having optimum security, a 6 quarts tub plus some aspen bedding in which they can bury themselves is often key.

You can additionally add a 6 inches plastic flower pot saucer as a hide, once will be enough.

As far as temps go I try to keep them at about 78 on the cool side and 88 on the warm side.

Warmth and security usually translate in hungry babies.

Limit your interaction with your animal at least until it has ate 5 times, the less interaction the less stress.

So if you switch your BP to something smaller give it a week before offering food and instead of offering a rat offer a live hopper mouse, something about the smell makes them more enticing.

Make sure you offer food in the enclosure.

If the first feed is a fail try again 5 to 7 days later, if this does not work the brown paper bag method will be what follow and if that fails depending how the status of your animal at that time you might need to consider assisting but that will be based on the animal's age and weight and general look.