The Block Under Header

First - go to WPBakery Page Builder > Role Manager and under the user roles, choose the post type is Custom and check the post type you want to use the WPBakery Page Builder (nasa_block)

Step 1 - Go to Static Blocks → Add New Block to create content

Step 2 - Navigate to Theme Options → Header and Footer to enable The Block Under Header section

NOTE: If you want to use the Elementor plugin to build the Block Under Header, please view a guidepost here