Third-party software and distribution
The plugin contains CEF (the Chromium Embedded Framework) and its runtime libraries; the licences of every component are in the plugin's third-party notices. WebUIStudio is distributed separately and carries its own licence material.
The sample uses the unmodified Geist, Geist Mono and Noto Sans SC fonts, Vue and three.js. Their licences come with the plugin and are copied into the page's build output; keep those files when you reuse the sample page.
The Type room also names nine fonts that Windows usually has (such as Segoe UI and Microsoft YaHei). They are referred to by name only; the plugin contains no file of theirs. Ship the fonts your own interface uses with your game, under a licence that allows it.
Everything else in the sample (scenes, textures, soundtrack and film) is original and generated by code. It contains no stock footage, sampled audio or assets from other games.
A packaged game contains the assets the interface uses, the page's build output, the Helper, the CEF runtime and the notices. It does not contain WebUIStudio.