You've landed on a SharePoint subdomain hosted by Microsoft, and technically that's a plus — the security setup is solid, the certificate is valid, and the connection is encrypted properly. But here's the question: who actually set up this particular site?
The domain ownership is hidden, there's no public track record, and the site immediately redirects to a Microsoft login page. If you're an employee or a collaborator who was explicitly given this link by someone you trust, this is normal SharePoint behavior and nothing to worry about. The risks change if this link came unprompted via email or text.
For a private business tool like a SharePoint document library or intranet, many of the missing signals (privacy policy, contact page, web history) are expected rather than suspicious. The real question for any brea-my.sharepoint.com link is whether you know and trust the person who sent it. If you don't, treat it like any unsolicited link: don't enter credentials unless you're certain of the destination.