AL wrote: do I have to notify dwp and esa about going into hospital for an operation , I will be in hospital for 3 or 4 days
Strictly, you must inform the DWP if you have a hospital stay, but it will not effect you benefits unless you spend more than 28 days as an in-patient, so they probably won't be bothered if you don't.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems