I don't know how to play this game at all, and there's no hint
If you click Notes on the side it has some hints for starting out. Priority 1 is to earn money and squirrel away anything that you don't need to pay for daily expenses into the bank to earn interest. You can earn money on your laptop, cleaning at home, or researching in the lab.
While working on earning money, go to the lab and run into Jimmy in the morning and after classes whenever possible so he can trigger his experiments to unlock more recipes. Once the events trigger you'll get a notice to talk to Jimmy, this will unlock a formula for pills. If you check your inventory, you'll find the recipe for the pills. You can buy the ingredients at the grocery store and mix them in the chemical lab. Use them on people liberally, both to see content and because it will reduce difficulty. For example, you can dose your bully to reduce how much he steals from you, and eventually stop him from stealing anything from you at all.
After that it's more the same. Earn enough money to buy supplies and upgrades, talk to people to unlock story progress and new pills, and feed everyone pills as soon as you get the opportunity to.