If you conuldn't find a font that you want to use from suggested fonts then follow below steps.

1. Open these two links on your tab bar : https://fonts.google.com and https://fonts.googleapis.com/css?family=
2. Find a font name that you want to use from first link page.
3. Write the font name at the end of url bar on second link page.(eg: http⁠s://fonts.googleapis.com/css?family=Example) and go to the link. (If you see error message at this step then check the name of the font again.)
4. From the page, find /* latin */ part then copy a url address which starts with http⁠s://fonts.gstatic.com and ends with .woff2

Example

/* latin-ext */
@font-face {
　font-family: 'Example';
　src: local('Example'), local('Example-Regular'),
　url(http⁠s://fonts.gstatic.com/Xjk5qpNj0LW-43aMEzIO6XUTLjad8.woff2) format('woff2');
}
/* latin */
@font-face {
　font-family: 'Example';
　src: local('Example'), local('Example-Regular'),
　url(http⁠s://fonts.gstatic.com/Xjk5qpNugdm0LZdjqr5-oayXSOefg.woff2) format('woff2');
}

5. Paste the link on Url box right next to "Provide your own" on this page.
6. Install or update theme.

Also you can upload your own font as well.
The font file will be not shared on online.