Honestly, how do you live and enjoy life?

Yesterday i've realized that I lived my life in vain and im lost since then. I dont enjoy anything other than video games, no friends, hobbies or anything. I developed so many problems over just 2 years and lost nearly everything about myself I considered to be a virtue, and I think that the reason why that happened is, I dont have what to live for. I never had a girlfriend, a true double-sided, healthy friendship, true dream and path under my feet. I just think, its not worth trying anymore (haha, I said that like I did try before this).

I did find a dream, I want to be a writer, but things I need to become are so big that now I see it as an actual dream, not a goal.

Im 18, 4th year high school which everyone finished but me (I have an F in math, with which I cant technically finish high school, about to take a general test in a couple weeks), and live in a toxic household.

What could I do to change this?