Fish from lake caught by father (8)
I believe the answer is:
flounder
'fish' is the definition.
(flounder is a kind of fish)
'lake caught by father' is the wordplay.
'lake' becomes 'l'.
'caught by' indicates putting letters inside.
'father' becomes 'founder' ('founder' can be a synonym of 'father').
'l' going into 'founder' is 'FLOUNDER'.
'from' is the link.
(Other definitions for flounder that I've seen before include "A fish; be out of depth" , "thrash around wildly" , "Be out of one's depth" , "Thrash about helplessly around the fish" , "Have difficulty" .)