Need gallery info please

Hi, I'm new here and am uncertain if this is the right place to post this question so here goes.

I'm interested in starting an art gallery but don't know the specifics involved in securing art for sale. Can anyone help me with this?

Does the selling of art in a gallery work on a consignment basis whereby the seller gets half of the profit? Or does the seller buy the art outright and sell the piece in their gallery accordingly? Any info would be appreciated. Thanks.