This domain appears to be an auto-generated internal file-sharing link hosted on the Microsoft SharePoint platform. It is not an independent website or a business storefront. When you encounter links formatted this way, you are usually looking at a specific file or folder created by an individual user within a corporate or academic Microsoft 365 environment. Because these links are generated for private use, the lack of a privacy policy, contact page, or verified business identity is standard for the platform but highly problematic if you were directed here by a stranger.
Technically, the site is currently inaccessible and presents a broken security certificate. This indicates the link has likely expired, Been deleted, or was improperly configured from the start. You should treat any request to sign in through such a link with extreme caution. If you are asking if 11066-ipv4v6e.clump.dprodmgd105.aa-rt.sharepoint.com is fake, understand that while the infrastructure belongs to Microsoft, the content it once held was managed by an anonymous end-user. Accessing unrecognized links of this type is a common vector for phishing, as they carry the credibility of a trusted domain while being used to host potentially malicious files.