Aurea
GrapheneOS does not recommend rooting, as it removes the security that Verified Boot provides (among other security things, I think). If you choose to root, then I believe its not considered to be "GrapheneOS" any longer and assistance will not be provided for issues you face, especially if you plan to install a custom kernel.
The website has instructions for building GOS if you wish to have your own modified version of GOS. Be aware that you are not allowed to call your custom build or refer to it in any way as "GrapheneOS".