Elevated skill, following one’s debut in commerce and trading (7)
I believe the answer is:
traffic
'trading' is the definition.
(I have seen 'Illegal trading' mean 'traffic' so perhaps 'trading' could also mean 'traffic')
'elevated skill following one's debut in commerce' is the wordplay.
'elevated' shows that the letters should be reversed in order (in a down clue, letters go up).
'skill' becomes 'art' (both can mean a talent).
'following' becomes 'ff' (abbreviation used in citations).
'one' becomes 'i' (Roman numeral).
'debut in' suggests taking the first letters.
The first letter of 'commerce' is 'c'.
'art' backwards is 'tra'.
'tra'+'ff'+'i'+'c'='TRAFFIC'
'and' is the link.
(Other definitions for traffic that I've seen before include "Moving vehicles; trade" , "several vehicles" , "Smuggle" , "Deals" , "Vehicles coming and going" .)