Noninvasive online virus sites?

Hi,

Years ago, like 25 or more years ago, I suspected a virus problem. Somehow I found an online virus scan site don't remember if it cost anything but it scanned the computer and told me where a virus was and I was able to delete it. Since then I've downloaded different virus protection softwear but always end up feeling that the program is very much like a virus itself. Are there any online sites that can scan for a virus and remove it without having to download anything and pay over and over again to keep it working but instead just pay when you need a scan and cleaning and otherwise not be bothered by it?

Thanks for any help!
David
Maine, USA