Maybe try something like this:
"Hi,
My name is Sammy Morales, I'm from Colombia. I'm going to be your new roommate. I'm really excited about our new English language school, but I'm also feeling a bit nervous. Maybe you feel the same way?
I'm nineteen years old, and I'm from Fusagasugá, a town near Bogotá, Colombia. My family is quite big, I have five brothers and two sisters. Do you have any siblings?
I really love sports and music. My favorite music group is ____. What about you, what are your hobbies? What kind of music do you like to listen to? I would really like to learn more about you.
I look forward to meeting you next month.
All the best,
Sammy"
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Your email was pretty perfect, you sounded very friendly and sweet, but also very formal, maybe use some of this version to loosen it up a little bit? I believe in you, and I hope your meeting goes well! I hope this helps some :)
