On the drink heading to North Country (5)
I believe the answer is:
niger
'country' is the definition.
(African country)
'on the drink heading to north' is the wordplay.
'on' becomes 're' (regarding).
'the drink heading' becomes 'gin' (I can't justify this - if you can you should give a lot more credence to this answer).
'to north' says the letters should be written in reverse (in a down clue, letters go up or 'northward').
're'+'gin'='regin'
'regin' back-to-front is 'NIGER'.
Can you help me to learn more?
(Other definitions for niger that I've seen before include "W. African country" , "22 across (anag) -- northwest African river" , "West African republic" , "Country in interior of N Africa, capital Niarney" , "Land-locked country and river of W Africa" .)