Hi,
the registry is the point where windows stores settings. You really shouldn't be poking around in there unless you know exactly know what you're doing. This can literally nuke your system.
A registry key itself is just a setting, not an executable file. Therefore, the registry key can't be a virus. It *could* however have been created by one (wich is unlikely though...)
Check your hard disk with some anti-virus software like Windows Defender/Windows Security and see if it finds anything. If it doesn't, you're probably good.