Create a new user and give them access through SSH public/private keys

linux_user_keys.sh

# Change to sudo
sudo su

# Export the username you want to create
export USERNAME=name
adduser $USERNAME
cd /home/$USERNAME

# Create the SSH keys
mkdir .ssh
vi .ssh/authorized_keys
# Copy-paste SSH public key into vi window

# Change permissions
chown -R $USERNAME:$USERNAME .ssh