You don't need to touch her tongue, just open bill and slide tube in. It works best for me if I start by inserting the tube on their left then aim diagonally across the tongue to their right. As the tube goes down their esophagus you should be able to see the feathers moving a little.
Go to this...
A pet store is unlikely to carry much, but an amoxicillin, Cephalexin, or maybe penicillin. @Patrick McKee , maybe ask your friend what antibiotics are given to people?