Is there a specific static page that you have in mind, or do you want to hide them from all static pages (e.g., About Moi, Artwork, How To, etc)?
If you want to hide the header image and menu for ALL static pages, you would add this CSS rule using a CSS plugin like Jetpack or Custom CSS Manager:
.page .site-branding img,
.page #nav-wrapper {
display: none;
}
If you want to hide it for a specific page, then instead of using .page in the selector, you would use the page ID that is associated with that particular page. You can see what the page ID is by going to edit the page. Up in the address bar, you’ll see a part of the address that looks like post=409. That 409 would be the ID that you would use like this:
.page-id-409 .site-branding img,
.page-id-409 #nav-wrapper {
display: none;
}
This rule would hide the header image and menu from only the About Moi page.