How do I change font size and style?

How can I change the font size of a text on a page? I want to shrink the size of a text, but I can’t find the options when I’m editing content on a page. I only see the options “Paragraph” “Heading 2” (and 3, 4, 5, and 6) and a few other fonts, but that’s it.

At first I used the “Heading 6” option, but it’s not the same font as the rest of the content on this web page: https://friendscpl.org/executive-speaker-series

I changed it back to paragraph form, but I don’t know to shrink the size.

Any suggestions?

Thanks!
Carolyn