Could you show an example to produce a key using the crate?

[asmmo]

Could you show how to produce a key to be used in ordinary cryptography works like sign and verify,..?

[burdges]

This is an elliptic curve crate, not a signature scheme or encryption scheme. You'll want some other higher level crate somewhere, depending upon what your doing, but most schemes build using this curve will not be beginner friendly.

[asmmo]

yes, I'm a beginner in this field, could you suggest some crate provide an interface for signing and verifying?

[burdges]

BLS signatures are extremely slow unless massively aggregated. Aggregation involves messy topics like gossip network topology.

Check out ed25519-dalek if you just need a signature scheme. RustCrypto project has some ECDSA crates too. Also ring.