Microsoft has deliberately hidden the auto-login checkbox for Microsoft accounts in Windows 11 because automatic sign-in undermines many modern security features (BitLocker, Credential Manager, remote desktop authentication). If you still choose to enable it:
In older Windows versions, the “Users must enter a user name and password” checkbox was always visible and functional for Microsoft accounts. (and recent Windows 10 builds), that checkbox may be hidden or grayed out if you are using a Microsoft account with Windows Hello (PIN, fingerprint, face recognition). To restore the auto-login option for a Microsoft account, you must first: netplwiz windows 11