It really depends which part of the U.K, or even part of the world, you are from.

For example, as a Uk Northerner who moved here, I find it is generally a little bit more expensive to eat and drink, not massively, but I suppose a Londoner would say it's about the same as home, or maybe a bit cheaper.

There are plenty of places to choose from, and prices to suit all budgets from McDonald's upwards.

I'm sure there will be a few others adding some recommendations to this thread for you in due course.