What your parents are going through is never going to be your fault. Your Parents have most likely talked and decided that this was the best decision for the family. You can talk to a guidance conselour or to close, trustworthy friends if you feel like talking, at first it may be hard to open up but trust me they'll listen and give you advice that they think works best for you.
Its also okay if you're a bit behind on school, it happens to everyone. Just try your hardest and focus on getting assignments turned in on time. With time you'll be finding it easy to complete and turn in assignments, never give up! I find working with students who also find it a little diffucult to turn in assignments is better to work with because you relate to eachother on a different level and its more soothing to open up or ask questions. Studying with a group also gets things done faster and is a bit better than working alone. But if you're not up for it thats okay you can always get help from teachers or the internet.
You're "friend" who is telling you to do D-r-u-g-s is not a real friend. Real friends try to talk or seek help for there friend. Friends should also never recommend something that could harm you in any way. Friends are there for eachother when thye need it most. You should never even think about or do d-r-u-g-s. They can lead to illnesses and death, it is danderous and unhealthy. Half of people who are addicted never get the help they need and it alos takes a huge effect on youre future choices such as your carreer and keeping friends and staying close to family. Im glad i could help, im here if you ever need anything. :)