Hi, grats on getting fastpanel installed - did you install it manually or use the 1-click marketplace option?

That option is here:
https://marketplace.digitalocean.com/apps/fastpanel

In the documentation for that option, it has the following regarding DNS:

Before you add a website to FASTPANEL®, we recommend connecting DigitalOcean DNS:

• Sign into FASTPANEL®
• Go to ‘Left menu’ - 'Settings’ - 'Basic’
• Open “DNS Account Settings” tab, then click “Add”, change “Type” to “DigitalOcean” and fill your API token.

You’ll need to create an API token in your DO cloud account:
How To Use the DigitalOcean API v2

Hope this helps but please let us know if you have any other comments or questions - good luck!