A quick search for "what babies need" on the Internet provides lists of products to buy. But in truth, many of the things that babies need don't come from a store.
From birth, infants need to know that their needs will be met.
Quick responses to a fussy baby tell her that she will have food when she is hungry, a clean diaper when she needs it, and that she will be comforted if she can't find a way to be peaceful on her own.
Although old parenting lore suggested that babies who were tended to quickly became spoiled, we know now that attention makes a child feel secure. Secure children develop trust and independence.