I don't know what I'm doing

Man, I need money. My car is rusting on the inside so bad, I was told that it wouldn't last the coming winter. I just finished high school, am starting an apprenticeship in August, and my sister is coming back from studying abroad. (We share a car.) I only have 50 dollars in my bank account btw. I don't know if I should sell some of my stuff online or in a garage sale. Or do some kind of omissions. I'm pretty good at pixel art, and doing stupid/comedic Photoshop. But I don't know. I might just sell some stuff. I have quite a few stuff people may want that I don't really touch anymore. I tried starting a monster-high collection, but gen one was too hard to get, so I started collecting gen three instead. But I still have 8 gen one dolls in really good condition, barely missing any accessories. I'd maybe sell some manga too. I have some stuff I wanted to buy, but changed my mind after finding out how long the series was. I- I just don't know. As the title states, I don't know what I'm doing... being an adult is hard.