<aside> <img src="/icons/info-alternate_gray.svg" alt="/icons/info-alternate_gray.svg" width="40px" /> **This is by far the best icon pack I've ever found! The icons can be used for commercial purposes for free, and there’s a lot of them. The site runs on sponsorships and donations.**

</aside>

Link: Commercial Free Icon Sets

To use an icon, download it and upload to Notion on a per-case basis.
The only place where you can't use external/custom icons in Notion is as property icons.
This icon website is the most complete free icon site I've ever found! There's something for every occasion.

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