Page in Old English helping process (9)
I believe the answer is:
operation
'process' is the definition.
(operation is a kind of process)
'page in old english helping' is the wordplay.
'page' becomes 'p'.
'in' indicates putting letters inside.
'old english' becomes 'oe'.
'helping' becomes 'ration' (I've seen this before).
'p' placed into 'oe' is 'ope'.
'ope'+'ration'='OPERATION'
(Other definitions for operation that I've seen before include "Procedure; enterprise" , "financial transaction" , "Handling" , "management" , "medical treatment" .)