Dumb question???

This may be a dumb question, but my husband and I got a “grow-with-me” car seat that doesn’t have a detachable base. So when we’re ready to leave the hospital with our baby, do we just carry her out? Do they do a car seat check? I kinda wanted my husband to do the “hot dad walk” but I didn’t even think about not having a specific newborn car seat. I’m a FTM so I already have no idea what to expect but I’m just curious!