Herb has drill and there’s silver in it (6)
I believe the answer is:
borage
'herb' is the definition.
(I know that borage is a type of herb)
'drill and there's silver in it' is the wordplay.
I cannot really see how this works, but
'silver' could be 'ag' (Ag is the chemical symbol for silver) and 'ag' is present in the answer.
'drill' could be 'bore' (synonyms) and 'bore' is located in the leftover letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
'has' acts as a link.
Can you help me to learn more?
(Other definitions for borage that I've seen before include "Blue-flowered plant with hairy leaves" , "Bag ore for the plant" , "Blue-flowered herb" , "Herbaceous plant with bright blue flowers" , "Aromatic herb" .)