As of 8/28/2017, the exchange rate between the US Dollar (USD) the British Pound (GBP) is $1.29 = £1.00, and between the US Dollar and the Euro (EUR) is $1.19 = €1.00. (It will cost you 1.29 USD to buy one GBP) So, keep in mind that if you want to buy a hamburger for the listed price of £2.50. or €2.50... it is not $2.50, but a little more. FYI, this is close to the best exchange rate in the past 15-20 years, so that a good thing!
We will gather 4-5 times during our stay in Europe to dine as a group. But for the remainder of dinners and a few lunches you will be on your own. I can provide further dining option details on request.
For the past few summers many students bought groceries and made some meals at the hostel (it has kitchen facilities for your use).