How to hide this area

You can try this

.site-header {
    display: none;
}

Adding css: https://docs.generatepress.com/article/adding-css/

Hi,there

Thanks for your help!

Do GPP have option to do that?

CSS is my second option

You can try setting the header padding to 0s: https://docs.generatepress.com/article/header-padding/

Or remove the entire header element with this filter: https://docs.generatepress.com/article/generate_header/

Thanks!!I think I will use css.

The filter method is as simple as copying and pasting.

Glad we could help!