This is my version.Dear John,
I miss you a lot. I haven't seen you for two months. It's a long time and I want want to see you once again to talk to you about everything.
I have heard that you have had a bad accident and now you are in the hospital. I heard that yesterday and I decided to write you a letter. Now I'm so hopeful to see you again and I hope you have a speedy recovery. ('and I wish you be healthy again' - it's repetition and wrong grammar).
Let me write short (I am not sure about this phrase, let native speakers check it) and I hope ('wish' is very formal) to see you soon. (you could write 'I wish you a speedy recovery' not to repeat the word 'hope')
thanks dear teacher
Student or Learner