One brings food in vehicle to sit around tree, unwinding (7)
I believe the answer is:
caterer
'one brings food in' is the definition.
'vehicle to sit around tree unwinding' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'to sit around' indicates putting letters inside.
'unwinding' indicates an anagram (to unwind can mean to break something apart).
'tree' with letters rearranged gives 'tere'.
'car' enclosing 'tere' is 'CATERER'.
(Other definitions for caterer that I've seen before include "Provider of food/drink" , "Refreshment supplier" , "One providing food and service for a party" , "Provider of food and drink" , "Terrace (anag.)" .)