A friend brings drink back (3)
I believe the answer is:
pal
'a friend' is the definition.
(pal is a kind of friend)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for pal that I've seen before include "Brother" , "Mate, informal friend" , "Bud" , "China" , "Friend (colloq.)" .)