For reasons that I don't remember, I have an old food coupon book in a folder labelled 'Important Odds & Sods' - see pic - so I dug it out and looked up Second World War rations online. Good lord - how did anyone survive?
From the Imperial War Museums website, I learned that every citizen was issued with a booklet to take to a registered shopkeeper to receive supplies. At first, only bacon, butter and sugar were rationed, but gradually, the list grew: meat was rationed from 11 March 1940; cooking fats in July 1940, as was tea; and cheese and preserves joined in March and May 1941.
Allowances fluctuated throughout the war, but on average one adult’s weekly ration was 113g bacon and ham (about 4 thin slices), one shilling and ten pence worth of meat (about 227g minced beef), 57g butter, 57g cheese, 113g margarine, 113g cooking fat, 3 pints of milk, 227g sugar (that's the same as the meat ration!), 57g tea and 1 egg. Other foods such as canned meat, fish, rice, condensed milk, breakfast cereals, biscuits and vegetables were available, but in limited quantities on a points system.
I also learned that apparently 60% of Britons told government pollsters they wanted rationing to be introduced, with many believing that it would guarantee everyone a fair share of food. I'll just leave that there for you to consider.