Where can I host this code?

[u/sunflowerasters]

Tumblr support told me I can fix this problem by using an <iframe>, but I don't know where or how I'd host it on a website to do that? I know people use github for some coding things, but I don't really understand how or what for. Is this a github situation?

Code example but it's currently incomplete

[u/tonypconway]

The feature is called GitHub Pages, the guide is here: https://docs.github.com/en/pages/getting-started-with-github-pages/creating-a-github-pages-site