How to get header/nav bar to stay while scrolling

I’m wanting the whole header/logo/navbar/motto to be fixed while the page scrolls up and down. I’ve tried to set the navbar and logo to a “fixed” position, but once I fixit it throws the spacing of the motto off. The navbar is broken up in left, right, middle pieces. Is there a way to maybe put it all in a “container” to keep everything like it is and not move when scrolling and the content can just disappear behind it and not show through. I’m using rapidweaver 5 and the Final theme. What direction do I need to go. Thanks