I'm scared to sleep at home alone
Why is that scary to you?  Do you usually sleep with someone else?
No, I don't like to sleep next to someone, I just like knowing someone else is here.
Adults are expected to be self-sufficient, but it's okay to not want to be alone at night.  If you don't like to sleep right next to someone, maybe you could find a roommate.  It would make you feel better to know that someone else is in the house with you.
Where should I even find a roommate? I'm only 20 years old. Again I don't need someone sleeping next to me, just someone has to be around there. It's not like someone will break in, right?
Well not wanting to be alone is normal I guess. You could ask a friend to be a roommate you don't need to be romantically involved for this if that was your thinking.