Hi, a VPN has a specific purpose, which is to change your on-ramp to the internet. Let's say you connect from home. Websites send responses to the IP address assigned by your service provider (whether wired or wireless). The IP address is associated with a particular geographic location, although not usually as pinpoint as if you give location permission. Your geographic location can affect the response from the site. For example, Google may serve search results tailored to your location even if you use one of its sites in another country. BBC may block access to content for visitors from outside the U.K. And so on. When you subscribe to a VPN service, websites see your connection as coming from a different network. Often you can choose whether your on-ramp is a few states away or across the globe. And that can change the responses you get from the site. Using a VPN also can make your online activity more private by making it more difficult to trace requests back to you. Unlike your local ISP, which might be required by law to keep records of your browsing, most VPN providers try to minimize those records. Political dissidents may find it necessary to use a VPN due to speech and access restrictions in their countries. One other benefit of a VPN is connecting safely over public networks. You can't always be sure that "Free Airport Wi-fi" isn't some dude in the next chair spying on everyone. When you run a VPN, your system doesn't need to rely on the local network provider as much. So that is what I think a VPN is useful for. It could be handy in many situations, but isn't essential for most people. As for antivirus software, Windows 10 includes Microsoft's Defender product. You can research reviews out on the web about what additional benefit you might get from a paid product.