If you have an account with nostr:npub1getal6ykt05fsz5nqu4uld09nfj3y3qxmv8crys4aeut53unfvlqr80nfm you can scan the QR code from the https://getalby.com/node page where it says, “Show your connection credentials”

It can also be used to connect to a self-hosted node like nostr:npub1aghreq2dpz3h3799hrawev5gf5zc2kt4ch9ykhp9utt0jd3gdu2qtlmhct