To install the New Outlook via command line, use winget in PowerShell for the Store version (winget install -i -e --id=9NRX63209R7B) or the Office Deployment Tool (ODT) with a configuration.xml file for enterprise deployments, running setup.exe /configure configuration.xml, with options for silent installs by adding /q and escaping quotes if needed. The New Outlook is also now part of Windows 11 (24H2+) and can be deployed via ODT or as a Windows App Package
winget install -i -e --id=9NRX63209R7B --source=msstore --accept-package-agreements