One possible version：

Tom,

I’m very glad to receive your letter. And it’s a pleasure to tell you something about how I will spend the Labor Day holiday.

First, I want to have a good rest because I feel tired due to my heavy study burden as well as lack of sleep and physical exercise. Of course, I’ll spend two days staying with my grandparents living in the countryside, helping them do some housework and telling them what has happened to me and my friends. If possible, I’ll have a trip with my friends to appreciate the beauty of nature and breathe fresh air. What do you think of it?

Best wishes

Yours,

Li Ping