How can I be a normal person?

Im the most naive eighteen year old female there is. I know nothing. I've lived a pretty sheltered life. I dont know how to converse with people and I often find myself in awkward and uncomfortable situations. I tend to avoid confrontation. Also, I speak in broken sentences....my words dont make sense and it doesnt come out the way I want it to. I am extremely right brained, I dont even think the left side of my brain functions...I'm pretty slow, even in my speech. I'm clumsy...I have adhd...among other things, I'm sure. It takes me awhile to catch on to things, and I usually have to think hard, I always find myself admiring clever, articulate people and disliking myself for not being like that. I dont have a lot of friends, Ive never been in a relationship....in fact ive never even been kissed. I dont get out of the house often enough to experience anything. everyone I know is growing up and moving on but I still feel like im eight years old. I dont even feel confident enough to be in a relationship because Im such a baby, who would want to be in a relationship with me? a proper relationship? I dont even think i bring anything to the table.....I dont know a lot of basic knowlege and I feel less smart than others, I've heard children half my age speak more properly than I.