How to change custom header image size

Hi guys, I tried to change height of custom header image, but it doesn’t work.

I have a widget to display different header on different page.
The size of per page image is different than on the home page that is built in the theme itself.
This is header on the home page: https://thecouplesbusiness.com (its size is fine with me).
Than there is individual page: Could you please see here? https://thecouplesbusiness.com/work-with-us-couples-business-coaching-training/
That’s where I want to change the height.

Question 2:
Also, If I want to add a Vmeo or Youtube code to add a vidoe in the header, how can I do that?

Thank you very much.