Talk about your best friend. How would you describe him /

I have a lot of friends, but also i have one best friend. Her name is Olga. She is with me in one class. Every day we are walking together to the school. She lives close to me in neighbor building.
My best friend has long brown hair and blue eyes. She is middle-height and slim. She is 12 years old like me. Her birthday on 21 of February.
My best friend Olga is very funny and kind person. Also she is friendly and cheerful girl. We like to spend our time together doing homework or playing.