What should I do when my best friend is taking advantage of me financially?

Why do some people believe it's important to buy groceries or pay for things when staying at a family member's house? Is it really about the money?
Should reporters be held accountable for trusting Joe Biden's claims about his mental and physical capabilities?
This boy at my school started talking to me through IG, I caught feelings and told him but he rejected me. He sent me a reel about relationships. How do I reply to it?