Turning 18

I am turning the age 18 in a few months and I feel so stressed and heavy in my heart. It's hard to comprehend that I am turning a legal adult with more responsibilities upon me especially considering the fact that I am still basically the carefree teenage 15yr girl reading yaoi in her room all day. I haven't made much improvement in my life I can even say that it got worse, not in the sense that I am depressed or anything but my social skills got so much worse, I barely have friends i keep in touch with. Life is moving so fast for me and I don't even have any stable plans for my future, I'm also so average in my studies I'm hopeless in the academic line.
Please feel free to give me an advice as I am so lost in this game of life with no purpose and no direction to follow