On Windows 11, you can configure virtually any computer application to launch automatically during startup using the Startup ...

Windows 11 Start-up Programs Explained By managing which applications launch during boot-up, you can significantly reduce the time it takes for your computer to become fully operational. First ...

Here, you can browse the list and select on an app-by-app basis whether each app should be automatically launched at system startup. Simply toggle the button for Microsoft Teams to Off.