Hello Amin,
Windows Security is built-in to Windows 10 and includes an anti-virus program called Microsoft Defender Antivirus. If you have another antivirus app installed and turned on, Microsoft Defender Antivirus will turn off automatically. If you uninstall the other app, Microsoft Defender Antivirus will turn back on automatically.
To customize how your device is protected with these Windows Security features select Start > Settings > Update & Security > Windows Security
You canTurn Microsoft Defender Antivirus real-time protection on or off by following the below step,
1.Select Start > Settings > Update & Security > Windows Security and then Virus & threat protection > Manage settings. (In previous versions of Windows 10, select Virus & threat protection > Virus & threat protection settings.)
Open Windows Security settings
- Switch the Real-time protection setting to On/Off and choose Yes to verify.
To Get to know more about Windows Defender antivirus click the below link,
https://support.microsoft.com/en-us/windows/stay-protected-with-windows-security-2ae0363d-0ada-c064-8b56-6a39afb6a963
Hope this answers all your queries, if not please do repost back.
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