Microsoft ships an antivirus named Microsoft Defender with Windows 10. It scans for malware in the background, but you can also perform a full-system scan with Defender…

If you haven’t tried Defender before or if your computer is acting funny and you’re worried about an obvious threat, it’s best to start with a Full scan.

Learn How to Scan with Microsoft Defender Antivirus on Windows 10
@ HowToGeek