alright how do I go about fixing the telescope I think I figured out part of it I ended up getting the plunger and used it on the telescope at general grants and then it broke and now I’m stuck what do I do next so i can get to the dragon boss?

I tried, I even spent my money buying those scrolls that boost the weapons I don't use, even this part has a bug, because I spent all the money without knowing that it wasn't accumulative, I was buying and not understanding that you can only use one type, and I still couldn't beat the dragon