Welcome to Nostr. What client are you using? Nostr has this cool thing called Zaps when people send Bitcoin through your posts.
Its really easy to set up just download Wallet of Satoshi from the app store
https://apps.apple.com/us/app/wallet-of-satoshi/id1438599608
https://play.google.com/store/apps/details?id=com.livingroomofsatoshi.wallet
Open the app click Receive
https://nostr.build/i/8c001704a8ff18663cf3d63ae9be03a9a9bb149b1cff2ebc344ac2a43c9b3f4b.jpg
Then click the lightning address
https://nostr.build/i/df8389ff20d1b4019d95bb7213f7023a13ffccf950d4218ab5c3d96e255afbfb.jpg
It should now be copied. Go to your Nostr profile and paste it where it asks for a lightning address. Now people can send you some bitcoin ⚡️