Petsmart Feeder Goldfish?

Howdy yall! I recently purchased this silly feeder fish from petsmart for 23 cents! I'm assuming he's some kind of goldfish? I have him in a temporary tank right now while a bigger one comes in the mail. Does anyone know what kind he/she is? I’m 98% sure he’s a comet goldfish?

Any care/feeding tips would be amazing!

Right now he/she eats half tropical fish flakes half blood worms but i'll get specific food if anyone has suggestions!

What’s the best substrate for them? I have black sand in his temporary tank right now

I might get him/her a friend once the bigger tank / better set up is done

Thanks!