Thousand supporting America in the French location in Africa (6)
I believe the answer is:
lusaka
'in africa' is the definition.
('Lusaka' is part of 'africa')
'thousand supporting america in the french location' is the wordplay.
'thousand' becomes 'K' (synonyms).
'supporting' means one lot of letters go next to another (in a down clue, some letters go below others).
'america' becomes 'usa' (synonyms).
'in' means one lot of letters goes inside another.
'the french location' becomes 'la' (I am not sure about this - if you are sure you should believe this answer much more).
'k' put after 'usa' is 'usak'.
'usak' inserted into 'la' is 'LUSAKA'.
Can you help me to learn more?
(Other definitions for lusaka that I've seen before include "African capital - UK alas (anag)" , "Capital of Zambia" , "Zambian capital" , "Central African capital" , "Zambian city" .)