Informal email

Hi John,
Thanks for your email, it was great to hear from you. Sorry for not writing earlier, but I’ve been ill because last month I injured my leg playing football with my friends, so I couldn’t write to you an email because I had to go to Seville to recover completely from the injury.
Now, I’m fine and I hope you are well. Good luck with your classes at the university and I wonder which degree you are studying for. Furthermore, thank you for worrying asking (o, for your concern) about my family, they are very well and I hope your family is well too.
Nowadays, I am having taking classes at the university too and I am planning to go skiing with my friends to Sierra Nevada this winter, so when I know the date of the travel trip I will tell you and if you want we can have dinner anywhere somewhere in Granada.
I also want to tell you that there is a race here the last week of December and we can sign up to run this race together.
Looking forward to hearing from you soon.

Regards,
Mario

Very well written.  

"worrying" implies that something was wrong in your family and your friend was very concerned about it.

"anywhere" = dondequiera, but I think you meant "somewhere" = en algún lugar