I'm trying to issue a Let's Encyrpt certificate for a web app I'm hosting on my computer, and the verification method (DNS records) requires this:

Action Required: acme-dns DNS API :: [Action Required] To complete setup, add a CNAME record in your DNS:
_acme-challenge.dragonosman.dynu.net
with the value:
18e39bca-a87d-40a4-b08d-724a39489335.auth.acme-dns.io

How can I do this? This is my first time doing it like this, so any help would be appreciated. Thanks.