Hi,
If I were to create a project that is in 'early development' option to just share devlogs and a demo , does it means that my project is officially launched on Itch.io?

Thanks

If you set the page access to Public, then yes, it counts as released, showing up in searches and whatnot.

In addition to setting the visibility to Public as mentioned above, we have different "release status" options to set how far along in development your project is.