How to structure h1-h6 tags?

Question

Search Engine Optimization

Hello!
Faced such problem as structuring tags h1-h6.
As far as I know, in an article, for example, you cannot use the h2 tag after the h3 tag. Everything should go in turn h1, h2, h3, etc.
But what if I have h2 first, then h3 subheadings, then another large h2 heading and h3 in it too. Sometimes there are even articles where you need to use h4. Okay, I replaced h3 with just a bold selection, and when h4 is there, I don’t know what to do at all.