On Windows10 follow this tutorial:
On Mac/Linux:
If you don’t have one yet, you’ll need to create one. Open a terminal and run:
ssh-keygen
Follow the prompts to give the key a name and save the key (or accept the defaults). You are advised to protect your key with a passphrase.
Generating public/private rsa key pair. Enter file in which to save the key (/Users/USER/.ssh/id_rsa):
This will generate two files (in /Users/USER/.ssh/ , if you accepted the defaults). id_rsa is your private key, and id_rsa.pub is your public key. It’s the contents of the public key file that you’ll need for this form.
To output the contents of this file to your teminal, run:
cat ~/.ssh/id_rsa.pub
You can copy this output and paste it into the form on Bryn.