Are you wanting to change the colour of the “Page” headings? I was thinking you were referring to blog posts…however, if for page titles/headings, if you go to the theme options with the customizer, on the Colours tab, scroll down until you find “Page Headings” and then you can select your colour. I’m assuming you know where the theme options are?
As for your question about the
tag, I’m not quite sure what you are referring to?