Will he go far? (5)
I believe the answer is:
miles
This might be a double definition.
'will he' is the first definition.
'Miles' can be an answer for 'he'. I am unsure of the 'will' bit.
'far?' is the second definition.
(mile is a unit of distance)
'go' is the link.
Can you help me to learn more?
(Other definitions for miles that I've seen before include "Imperial units of length" , "'But I have promises to keep, and . . . . . to go before I sleep' (Frost)" , "a long way" , "Distance units" .)