To make the header section sticky, where the header always shows on the page while the user scrolls down, you can enable the sticky option.
Open the page that you want to edit. Click on the header section to open up its properties on the left. Scroll to the bottom of the settings and tick the Sticky to check box. Select Top.
Save the changes. In the preview or live mode, you will now notice the header will stick in place and always be visible even when you scroll down the page.