I am Win 10 (64) latest (non preview) version.
I back up to External HDDs and also USBs (also take USB to Print shop for printing)..
On my current laptop, new since Sept 2020, I use only Windows Defender for protection.

I cannot find a way for it to scan my USBs or external HDDs.
Can someone guide me?

I should prefer not to have to go back to my old laptop scenario where, in addition to Win Defender, I used 360 Total Security to be able to scan such devices