Understood what’s ahead of Daniel, heading off to join the navy? (2,2,3)
I believe the answer is:
go to sea
'join the navy?' is the definition.
'understood what's ahead of daniel heading off' is the wordplay.
'understood' becomes 'got' (getting is a kind of understanding).
'what's ahead of daniel' becomes 'hosea' (book of the Bible after Daniel).
'heading off' means to remove the first letter.
'hosea' with its first letter taken away is 'osea'.
'got'+'osea'='GO TO SEA'
'to' is the link.
(Other definitions for go to sea that I've seen before include "Leave working on the land" , "live off the land" , "Become a sailor" , "set sail" .)