I am not feeling motivated

Even now, as I am writing this, I should be doing homework. It seems as if everything there is a lot of work put in front of me, I shy away from it and instead watch completely useless videos or read random news articles. I can't seem to find focus at home. And then, I go to school, and obviously, it gets worse.
I used to love going to school. I liked the material, the teachers, the extracurriculars. I thought my school was amazing because after 8th grade, we do college material there in almost every class. I thought my school was special.

Recently, I found out that some people in the grade above me take drugs. People tell me I should have seen it coming, but I really believed that the people in my school were different, that they were smarter than that. Lightly put, I was devastated. We did a drug unit in my chemistry class. I know this seems funny, but I actually took it seriously. I learned about people who trashed their lives taking drugs, who gave up their family and job and success to drugs. I couldn't believe that people had learned about drugs in school and still took drugs Later on, I found out that people in my grade take drugs. One of my friends, he did too. I asked him why. he tried to convince me that what I learned about drugs was far from the truth and that taking drugs wasn't actually that bad. But to me, it is. It is that bad.
Call me unreasonable if you want, but I learned about these drugs. I know everything from the molecular formula to street names to cases in which young kids have died from overdosing. The people around clearly don't think so, but It is a serious problem for me.

My school is very small, so knowing that people I have been going to school for the last 6 years have been taking drugs all along makes the whole school experience terrible. I don't really have any friends, which makes the school experience the worst ever.

I can't focus at home and I'm depressed at school. If i had to diagnose myself, I believe I'm need of a little inspiration.