I've tried Jekyll in the past but the setup is a bit overwhelming and it gets complicated super fast. I am looking for something where I can keep my header and footer separate and then include them in every other page. That's it. No CMS and no blog. Is there something which handles this well and is easy to set up?
I use Cloudflare Pages to host my website
With SSI, your template for every page would basically look like this:
Making your own SSG is another good solution. They're easy to make, and you can tailor them to your own particular needs.