Drumstick diva is right...the Learning Center will get you off on the right foot with your chickens. There are articles on all things chicken (including feeding). Here's a link to get you there: https://www.backyardchickens.com/atype/1/Learning_Center
I'm glad you joined the flock!
As drumstick said visit the learning centre
You can feed them layers pellets.
You can get this from a co-op or farm store
You can also feed them greens and kitchen scraps etc.
You would only shower or bath a chicken if you plan on showing them
Hope this helps