How to connect to a remote server if the username and SSH key are available as a string (apparently incomplete)?

Question

SSH

It is necessary to connect to a remote server via SSH
The customer provided a username and not entirely clear SSH keys in the form of a regular string
-----------------
user: ssh_user
keys:

ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAQEA366rtRt56Tgfh9joY7FtkUC/rXU/yMJR+kGMFT4u8riYhG5KzqGYB+pWl5X+JUsKEkR2dfkaEMSscf1fZz2AvJZoQVUyMkv6Cv31ay4dN4vBm366rtRt56Tgfh9joniIkOntdAnVPJ6UP7Hs3wmtiwhIJLRSZdTkyHMv1nkJlQEBRJrwXL8VMc+366rtRt56Tgfh9joRoC366rtRt56Tgfh9joZvdoIHRfRlLN366rtRt56Tgfh9jovuCY7XQo1zAtWkOc9Zie1KXfelDBVFB2S/sokdLCjz8t6fzePhYC5D6Ln/24366rtRt56Tgfh9jojGpGHwcOBZ9BzfmIA0Wnm++xG8366rtRt56Tgfh9joFBK0teFiev7V+ipw==
ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAQEA1B+jA366rtRt56Tgfh9joY2/pSVhnx2+1+mr6EyecRhf1ksh2W69Lhrc57eLwELQbbgmXePWf3yrwOz/1HhbG366rtRt56Tgfh9joV3rE54M0wYlWuUar5GYCujwjRhaZYacPWGaBY0GyP3x5+C6dn10Marh3A7yJw0Anh1Zsi0bHqV4YQkPKAaO4iVWrS0wrtYRTYretyRE366rtRt56Tgfh9joFGHTrbHhy05IfR7xd92X366rtRt56Tgfh9jo+9wMkNqJZ366rtRt56Tgfh9joWNR3bk4uHjpL+2zCR62p+366rtRt56Tgfh9jo+6ulJzKCB072Pr9+m2YrLKS366rtRt56Tgfh9joNdtW3+lhThgvM5V+enc5Q==

the second day I can’t figure out how to connect to the server, I
tried to write the contents of the key as it is to a file like key.pub, but it didn’t help

Answer 1

These are the public parts of the keys, which are located in a file ~/.ssh/authorized_keyson the server, and the ~/.ssh/private parts of the keys should be in the local directory. It should be the other way around: you provide your public key, and the server owner adds it to authorized_keys , and after that it will be possible to access the server via SSH. So generate a key and send the public part to the client - and nothing else. The private part of the key must not leave the PC on which it is used. When sending a private part of the key over an unencrypted channel on the Internet, this part is considered compromised and this key must be destroyed.