The babies will need to shed immediately. An ice cream bucket works well with a little warm water in it. These babies will also be thirsty. Dehydration is a big concern for neonates. After they shed they can go into something tall with a water dish and something to hide under. A piece of cardboard with two ends turned down works great. Even a piece of paper will work for a hide.
Do you know what species garter you have? Where are you located?
Here is a link to the forum care sheet which would answer many of your questions. Anything not covered feel free to post on the forum.
We would love to see a few photos of the adult so we can ID it for you.

Garter snakes don't eat crickets/meal worms or any other type of bug.
A diet of rosey minnow can cause a B1 deficiency because of thiaminase(this is covered in the care sheet)

Be sure to introduce yourself in the "Welcome Lounge" once things settle down.

Garter Snake Forum - Garter Caresheet

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