Old prune in deep content to perform (7)
I believe the answer is:
execute
'perform' is the definition.
(I know that perform can be written as execute)
'old prune in deep content' is the wordplay.
'old' becomes 'ex' (prefix meaning former or onetime).
'prune' becomes 'cut' (synonyms).
'in' is an insertion indicator.
'content' indicates the central letters.
The middle letters of 'deep' are 'ee'.
'cut' going inside 'ee' is 'ecute'.
'ex'+'ecute'='EXECUTE'
'to' acts as a link.
(Other definitions for execute that I've seen before include "Guillotine" , "Put to death - put into effect" , "Maybe send to chair" , "Get it done" , "Discharge" .)