Is there an app that we can add to gempages (shopify) to create a header and not having to deal with shopify's ones?

I'm currently working on a shopify website where I use Gempages. I'd like to change the header. I know I can unactivate it via Gempages and create a new one that i'll just have to copy/paste on every pages as a simple block. But for any modifications, it will imply to do it on every pages... So i'm earching for a more simple solution (if there is one ) that offer drag and drop, or i'll just have to code it (I'm a kinda new dev, and this looks painful to me ) Thank you in advance for those who will take time to reply, this community is always a great help. :)