To make a gift when out of breath, must be a struggle! (5)
I believe the answer is:
fight
'a struggle' is the definition.
(fight is a kind of struggle)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for fight that I've seen before include "Brawl; argue" , "Box" , "Contend" , "Strive - struggle" , "Contest" .)