SSH를 사용하여 연결할 수 있도록 원격 서버에서 로컬 컴퓨터로 개인 키를 올바르게 복사하는 방법

First don't put your private key on the remote server. Any one compromising this server will have all access that you have.

Now that is out of the way. You have two options.

1. Create a new private key on your new local machine. Then copy the public key (it comes with the private key, or can be generated from it). to the server. If goes in ~/.ssh/authorized_keys, one per line, so append it, don't overwrite the old one (or use ssh-copy-id).
2. On the old local machine. Using putty, tell it to export your private-key in open-ssh format, then copy this to the new local machine (running openssh). It goes in directory ~/.ssh/ mine is in file id_rsa.