Step 1 -   Run the   ssh-keygen -t rsa   command

You can use the -t option to specify the type of key to create.

For example, to create an RSA key, run:  ssh-keygen -t rsa 

Step 2 -  Save file
The command prompts you to enter the path to the file in which you want to save the key.

A default path and file name are suggested in parentheses. For example: /home/user_name/.ssh/id_rsa. To accept the default path and file name, press Enter. Otherwise, enter the required path and file name, and then press Enter.

Step 3 -  how to read generated rsa file

if the file name of the SSH private key is id_rsa, the file name of the public key would be    id_rsa.pub

Read private key using  Syntex cat in command prompts /terminal.   cat  id_rsa.pub  or   /Users/admin/      cat .ssh/