I recommend aquafor for diaper rash, works great and can be bought at any drug store in a big tub. Aveeno baby shampoo is great unscented.
Get smaller sizes of these items before the baby is born and see which one works best for your baby and their skin before you buy too much of one product. Buy in bulk after you determine which works best for your baby!
It’s all preference, but they sell kits on amazon for first time mamas with all this stuff.