I'm afraid of my former friend
Why are you afraid of them?
I don't want to deal with him. He's always contacting me when I'm out with my friends.
It is your choice on responding to your friend. There is no reason to be afraid of them though if they just want to get into touch.
I guess your right but I'm surely going to avoid him
If you truly want your friend to leave you alone then you should tell them. This will probably fix your situation quicker anyway and leave you feeling less stressed.