Step 1: Log in to Windows Store for business: https://businessstore.microsoft.com , I don’t write details here how you have access rights for this. In top right corner search for “Microsoft Whiteboard (Preview)“
Step 2: In top right corner search for “Microsoft Whiteboard (Preview)“
Step 3: Find Microsoft Whiteboard (Preview), choose License type Offline, then click Get the app
Step 4: Go to Products & services, open Microsoft Whiteboard (Preview)
Step 5: Choose Minimum version 1607, Architecture X64. We choose minimum version 1607, because Windows Server 2016 is version 1607, it won’t work if choose other version.
Step 6: Download the whole package and the required frameworks
Step 7: You should have 4 Appx files in your download folder
Step 8: Run PowerShell with elevated privileges, use Add-AppxPackage command install required frameworks, then install Microsoft Whiteboard (Preview) app.
Step 9: So now you have Microsoft Whiteboard (Preview) installed in Windows Server 2016