As others have said, this really is a "how long is a piece of string" type of question.
"likely Bristol or nearby" - this is going to be the biggest thing. I guess that you have family in Bristol? Bristol is stupidly expensive. Literally any other town or city in a 30 mile radius is going to be cheaper than Bristol.
For example, this three bed, 1,300 sq ft (120 sq m) terraced house (often called a row house in the US) in the decidedly unglamorous area of Brislington:
https://www.rightmove.co.uk/properties/153767807#/?channel=RESBUY
is typical of many houses in Bristol. (I used to live very near to this house many years ago). It's currently on sale at £475k or US$615k
When it comes to food, that's a good thing. Whatever you're paying in the US, it's going to be cheaper in the UK.
When it comes to a car, things are very different compared to the US (unless you live in a very rural area, where cars are essential).
Your children will be able to walk to school or, if necessary, get the bus. That's not an issue.
The cost of a car varies - how much do you wish to spend? You can get cars on lease or buy them outright or with a loan. A good site to get an idea of the prices of cars in the UK is autotrader.co.uk They do used cars, new cars, lease cars etc.
For example, to take a discontinued car (that I happen to drive), in the US it's known as the Ford Fusion, but in the UK it's called the Ford Mondeo.
A top of the line 2022 petrol hybrid could cost as much as £22,000 (US$28,500) or a ten year old, 2014, Mondeo would likely cost you around £4,500 (US$5,800).
It all depends what you want.