can someone explain the requirements for changing an office building into a restaurant?

The quickest and easiest way is to talk to the planning officers by calling 273 4215.

Their is a webpage giving some basic information here:

http://www.sheffield.gov.uk/in-your-area/planning-and-city-development/planning-documents/otherinformation/hot-food-business

THANK YOU THANK YOU

i really appreciate that it helps alot