unknown minnow!?!?

what are those minnows that are always in schools and close to shore on sandy parts of freshwater

May times, those minnows close to shore are actually fingerling bass. Sure fire way to tell is by the distinct black tail. 99% they're mostly young of the year forage species (sunfich, perch, crappie, etc.)

I'm exploring little creeks and brooks. And small tiny ponds in my town.
There's no info on the Internet about places to catch craw dads or shiners and other bait!
So far ice found a place loaded with shiners. 2 dozen in an hour!
Found a brook with crawfish! And bass!

The funny part about the brook is. I drive by it everyday. Never thought there would be bass, sunnies and crawfish!

what are those minnows that are always in schools and close to shore on sandy parts of freshwater

Killifish

Banded killifish is most likely the bait fish you are talking about

Agree

yes they are defiantly banded killifish or maybe they are golden shinners but they are usually bigger between 3 and 12 inches