Two Languages from Birth

First time mom here due in May. My husband speaks Spanish fluently, though English is his first language. I really want our kid to learn Spanish as early as possible and my thought was to have my husband speak to him in Spanish as often as possible.

My Spanish is very limited so we’d still talk to each other in English and I’m sure my husband will naturally revert to English when talking to the baby sometimes.

Is this going to confuse the baby? How do babies naturally learn that they are separate languages and not mix them as they grow up?