open generated ssh key cat ~/.ssh/id_rsa.pub
what is public key
A public key is like an open box with an unbreakable lock. If someone wants to send you a message, they can place that message in your public box, and close the lid to lock it. The message can now be sent, to be delivered by an untrusted party without needing to worry about the contents being exposed. Once I receive the box, I'll unlock it with my private key - the only existing key which can open that box.