As in any language People's names start with big letter, countries, cities and nationalities also start with a big letter for always. Some examples:

My name is Andrea Durak.

I'm from London.

I'm in Stansted.

I'm English.

Do not forget to start with a big letter when you need to.

Dialog

-Hi my name is Andrea. I'm from England. What is your name and Where are you from?

-Hi my name is Elizabeth. I'm from Holland. Where about do you live in England?

-Andrea: I live in London. What is the capital city of Holland.

-Elizabeth: The capital city of Holland is Amsterdam.