h2 title
Use as the first title on a page after an H1 to describe a section. Good to follow up with regular text for SEO purposes.
If you don't use an h1 in the hero - make sure to use an h1 as the first section on the page.
For article pages - h1 is the title you set - so here you should just follow up with h2-h4 titles
h3 title
This you can use as a subtitle when you have an h2 above to write content in more logical order.
h4 title
You will probably not use this as much as h2 and h3 - but might be usfual if you have a long text with mutiple headings
p tag - fine print style. Used to add a small top-heading above an h2 for example