One nurse prepared to seek cover (6)
I believe the answer is:
insure
'cover' is the definition.
(I know that cover is a more specific form of the action insure)
'one nurse prepared' is the wordplay.
'one' becomes 'i' (Roman numeral).
'prepared' is an anagram indicator.
'nurse' with letters rearranged gives 'nsure'.
'i'+'nsure'='INSURE'
'to seek' is the link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for insure that I've seen before include "Rue sin (anag)" , "Take out a policy" , "do business at Lloyds?" , "Arrange for payment in the event of loss" , "Guarantee; make secure" .)