###How to add SSH key to server   
After setting up first remote ssh connection type from your PC (not server)  
  
` scp C:\Users\User.ssh*.pub user@hostname:/home/user/ ` 
(example: C:\Users\user*\.ssh\id_ed25519.pub user@ip_address_of_the_host:/home/)  
Then enter password, after that >  
Go to your server and add your key, to ssh_authorized keys >  
`cat id_ed*.pub >> ~/.ssh/authorized_keys `
And don't forget to restart ssh and sshd

Use this is password authentication still works (nano /etc/ssh/sshd_config.d/50-cloud-init.conf)