It is possible to setup a blockchaine project node on a raspberry3 and be rentable? What project do you recommend?
I wouldn't know how a Raspberry pi or the one you mentioned work because I haven't used any before. But as long as the raspberry has the capacity to run linux, windows or any other supported OS, then I'm sure you can run a node on it. If you're just running a full node without participating in consensus, then that's even better.
Regarding your question for possible projects to run the node for, you'd have to do your own research because it needs to be an incentivized Node otherwise, you're just running it out of the goodness of your heart. Do check out Avail, Espresso and a few others. You can use DeFi Llama to help with the research process.