Food
Do go to a pub and have a nice meal. There are very many pubs in London that do quite superb food. Here’s just one at random: https://www.thecadoganarms.london/
You may well need to book a table. There may be waitress service and an open kitchen. There will be a daily menu.
And then…
Some of the cheapest pubs offer long menus. There food will be pre-packed, perhaps frozen, microwaved and possibly edible. Certainly good value. These pubs may have special nights eg Thursday curry night.
Some pubs advertise home cooked food. This could simply mean it is bought in and then heated up. The microwave is your friend. Implies it is better quality but…
Then there is home made. This sound much better. You may see a line on a menu that “we serve home made food every day”. It doesn’t mean that all the food they serve is home made, just that something is. The implication is better quality and fresher, and that may be true…
Look for good gastropubs, places with kitchens, preferably open kitchens, with a limited menu of interesting food or the basics done astonishingly well. Here’s just one: The George.