Hi there,
you would need to add your H1 to your Page/Post content using the GenerateBlocks Headline Block.
You can set a different Highlight color:
https://docs.generateblocks.com/article/headline-overview/#colors
Which can be added to part of your text, by highlighting it and then choosing highlight from the 3 dot menu in the blocks toolbar.
For archive pages such as the Blog you would need to to use a Block Element to hook in your title:
https://docs.generatepress.com/article/block-element-overview/