Diaper bags/ Backpack

Trying to find a diaper bag that will work for us once baby is here in December. We have been leaning towards backpack style just for convince. This is baby #5 so we need all free hands available. Also our two middle girls are both autistic and allergic to many things so we mainly do meal prep at home and take with us which would also need to be put in bag, along with multiple medicines that have to be carried anytime out of the house. Any opinions or styles that other mommas have found to work or prefer?