How can I use a separate SSH key for Git?

Documentation FAQ
1

How to use a separate SSH key for Git

If you have more than one SSH key in use, you can configure SSH to use the right
private key by adding the following block to your SSH configuration in
~/.ssh/config:

Host repo.freistilbox.net
     Hostname       repo.freistilbox.net
     IdentityFile   ~/.ssh/id_rsa.freistilbox
     IdentitiesOnly yes

Simply replace the entry after IdentityFile with the actual path to your
private key file.

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