Oh, you can probably start with

GitHub

GitHub - nostr-protocol/nips: Nostr Implementation Possibilities

Nostr Implementation Possibilities. Contribute to nostr-protocol/nips development by creating an account on GitHub.

repository since there are many NIPs to learn 😅. You can probably pick some idea and start implement it even with simple PoC code, at least they can be useful for ourself. Hopefully we can create something better later for many people 🙂

Maybe try these, i am not a developer so i don't know, but people use it

GitHub

GitHub - nostr-dev-kit/ndk: Nostr Development Kit with outbox-model support

Nostr Development Kit with outbox-model support. Contribute to nostr-dev-kit/ndk development by creating an account on GitHub.

GitHub

GitHub - nbd-wtf/nostr-tools: Tools for developing Nostr clients.

Tools for developing Nostr clients. Contribute to nbd-wtf/nostr-tools development by creating an account on GitHub.

Yes, it will be easier to use those libraries to start nostr project instead of writing all the things from scratch 👍