Dear Ben,
  I am finally writing you a letter. We didn't talk for ages, sorry about that.
  Very soon, me and all my family are going to celebrate Christmas! I  am extremely excited  about that. Actually, I still need to do Christmas shopping: I still can't choose a present for my grandma. Two days ago, on Monday we decorated a Christmas tree and the whole house is now full with the spirit of celebrations. Tomorrow, me and my mum are going to start cooking: we need to prepare all the ingredients so we can easily make all our favourite dishes. I still don't know what Santa is getting me for Christmas, what about you?
  Have you started any preparation? What kind of decorations do you have in your house? What is your favourite Christmas dish?
Looking forward to hearing from you,
Merry Christmas,
(ТВОЕ ИМЯ)
P.S. I have a little present for you, hope you will enjoy it. It will be delivered to you by post within a few days, I suppose.

Hello, friend!
I want to told you about New Year.
New Year isn't very popular holiday in Europe and in America, but here, in Russia it is. I think, it is a very important holiday, because on the next day will be the first day of New Year.
At the 31st of December our family are at home. We give presents to each other and eat tasty things.
And what about you? What winter holiday do you like?