-написать письмо "устройство на работу в кафе"

I am writing to apply for a Restaurant Waiter position at the Blue Whale for June-August, as advertised in the newspaper. 

I am 16 years old boy and I'm at my (год обучения в школе, класс, ну например 10)th year of school.I am sociable, positive and hardy. So I'm interested in working with people. When I read your advert I understood that your work is perfect to me.

I have no experience in job like this, but I learn things fast. As I mentioned earlier I am at (снова год обучения, например 10)th year of school. I have pretty good marks in English, Russian and sport. 

If you are interested in my candidacy, please contact me as soon as possible.