Hi @rahulda2
Yes, it's possible to run two different projects (AEM + Google Docs) on separate codebases (GitHub repositories) while pointing to the same domain. This can be achieved by using CDN rewrite/redirect rules to direct requests to the appropriate origin.
However, editing pages created using document-based authoring in the universal editor is not currently supported, but it's on Adobe's roadmap.
Arun Patidar