Meta tags h1, h2 etc

Hello, I have a problem with the meta tags of my site.
Although I have applied h1, h2 etc tags to portions of text from the text/style tool, it seems that none of these tags are detected by either google or online tag search tools.

As a result, my site does not appear correctly in the search results at all.

Can anyone explain to me how I can correct this?
My website is decocapagut.fr