Can you correct my mistakes? An informal letter

Could you have a look at the following letter and correct mistakes?

Dear Mark,

Ho are you? Everyone is fine. My exams are over at last and I'm looking forward to summer. I'm writing to ask you if it would be possible to visit you in Melbourne this year. It will be a great chance for us to meet at last.
I'll be on holiday from the middle of Juny until the beginning of Semptember. August would be a good time for me to come, if it's okay with you. I'd love to see where you live and visit some of the places you're always telling me about. Maybe we could spend a few days fishing or you could teach me how to surf.
I'm really excited about the possibility of visiting Australia.
Please write back as soon as possible to let me know if I can come.
Love,
Kate

Thank you in advance

layla