RE: How to access back-end of E commerce for page editing in OneBox
Hey Muhammad,
I think you're in the wrong forum - this is 'connected store', which is a new offering (please see link:)
dynamics.microsoft.com/.../
Your question is related to D365 Commerce and to give you an answer, as of today we don't currently have a solution to enable the one box environments to access site builder portal as the new eCommerce and content management services are SaaS, cloud hosted offerings.
The product team are working on a solution to this so please do lookout for blog posts announcing when we will have this option.
For now, only Tier2+ environments can enable the full new eCommerce solution, therefore a customer implementation project is required. Sorry for that!