I like 360 safeguard antivirus it's completely free though nothing beats windows defender for me ehehehe.
I think, that free software is a bad idea especially for security. you pay nothing and get protection? what's the gain of the app? And as far as i have read, my concerns have place to be. Forbes recently shared a research made by some vpnpro on google stores free antiviruses, that do more harm than help. https://www.forbes.com/sites/zakdof...on-downloads-need-to-be-deleted/#332154d15c72 and here's the original research resource https://vpnpro.com/blog/free-antivirus-apps-requesting-dangerous-permissions-they-dont-need/ So long story short, I would recommend using paid antivirus ...because, free software is not reliable at all.
For Free Antivirus Software I always used AVG Free Edition. It was kind of the go-to on every system I worked with. Easy to find and download, worked-well and for free. I now have a paid anti-virus solution. But, AVG Free Edition has been installed on every prior system that I have owned. It was able to detect things and have them removed. I never had an issue with AVG Free Edition, its updates were automatic and did not require a new installation. Every year a new edition of the free version was released. Try that one - if you want to explore other Free Antivirus Software options.
I am using Bitdefender Antivirus, it gives me a great service. I still not find any computer lag or software crash.
Malwarebytes is the best free antivirus. it's light easy to use and catch most of the virus. You need to regularly update and can download it free.
Classical windows defender perfectly does its job actually. The vast majory of antiviruses can't protect your computer or laptop fully, if you are going to use free version I bet. So, you can just use standard windows defender and you must be sure that everything is protected carefully in your laptop. I believe that other antiviruses good, but they often have very high prices and there is a very little amount who can use them. Well, of course you can apply to the internet and find license keys for some antiviruses, nobody prohibits actually, but do you really need to waster your time just to search for an antivirus which you already have.