Combining two fields as Title

This page is using a H1 title and a H2 subtitle, but in the browser tab and in Google search, they are both showing up together as a Title

https://www.producthunt.com/posts/viable-2

https://a.cl.ly/9ZuxeelD

I have a custom post type where there is a title option, which is what shows up on the tab and google

I want to create a new CPT and import the old one to this.

For this new CPT, I want to achieve the same effect where there will be a H1 and H2 on the front end, but they both will be joined as the title. This way I can position the h1 and h2 in different areas but have the benefit of it being the Title

How do I achieve this?

Thanks