Login to cPanel and click SSH Access

Click on Manage SSH Keys

Click on Import Key

In the field, Choose a name for this key type in: id_rsa

Leave the fields blank – Paste the Private Key in this box and Passphrase

Open Terminal and add the following command

/home/USER/.ssh/id_rsa.pub

Or On your local computer, open the file, /home/USER/.ssh/id_rsa.pub

Copy the content and Paste in to Cpanel’s import key page – Paste the Public Key in this box

Click Import

After adding Click on Go Back button

You can see The key named id_rsa.pub was imported. Click on Back to Manage Keys

For authorising the key click Manage and then click authorize