Though Spanish is the main language in this country, Spain has many dialects depending on where you are. For example, in Madrid, people primarily speaks castellano, but in places like Barcelona, which is in Catalonia, many speak Catalan. Other languages within Spain include Basque, Galician and Andalucian.
Euros, similar to many other countries in Europe, are the main form of currency, here. The currency symbol of euro is € or may be written as EUR. The value of the euro is higher than the U.S. dollar, so the conversion rate is a bit rough for me coming from America!
The price of a bottle of water averages as 1 euro. One important tip would be to ask for agua de grifo, which is free at restaurants, as they may bring bottles of water that they may charge for without requesting prior.
My host mother is an amazing cook, so having meals at home has been affordable, tasty and has taught me lots in regards to Spanish cooking techniques and daily meals. We frequently consume lots of potatoes, vegetables and garbanzo beans, as well as salad.