Titles on Google

Hi there!

Our site is only few weeks old, so I’m not sure if this is happening because of that: maybe our site isn’t indexed totally to Google.

But my question is: when I write the title of an article/post and/or Focus keywords on Google, instead of the article/post title, it shows the headline of our site.

Example (just out of my head):

It shows: RankMath – Your perfect SEO partner (the site name)

And it should be (again, just out of my head):

Here’s your perfect guide for SEO (post title)

AND for some reason instead of the actual description, Google shows article image’s alternative text.

Might it be, because we didn’t do anything for the Rich Snippet on my post? We’ve done all the SEO setup in the article editor, except for the rich snippet.