You need the model and the 11 digit Product number (PNC) - or 12 digit service number - which is displayed on a sticker or data plate For cookers and ovens, this is usually behind the oven doors (around the frame). For hobs this is usually on the underside, side or back of the appliance.
Here's What you should See
Your model number may be a combination of letters and numbers. The Product number (PNC) will be 9 digits followed by a (/) or "space" and ending with 2 numbers. The service number will consist of 12 digits starting with the numbers "85"