What does WSDaemon.app do in my computer?

If it was installed with the Webroot Secure software that you initiated, then leave it in place.

If you have already uninstalled the WS software and this was left behind, then yes, it is safe to remove.

Without the WS software it is neither benign nor useful and should be removed.

If you need additional removal guidance, you should visit the Webroot Secure support website.

As far as I can tell it does nothing that you cannot do yourself for free.

I've been using and supporting Macs since 1986. Within my circle of family, friends and coworkers we've never discovered a need for apps of this type.

Among other things, Webroot Security claims to be an anti-virus for Mac (there are no viruses on the Mac platform),

claims to protect against phishing websites and ransom-ware, claims to monitor your firewall and to secure your smartphone and tablet. WS claims to do these things, but there's little basis for their claims.

It's good for separating a user from their money. That's about it.

Please, see these support documents:

Protecting against malware in macOS - Apple Support:

https://support.apple.com/guide/security/protecting-against-malware-sec469d47bd8/1/web/1

XProtect Explained: How Your Mac’s Built-in Anti-malware Software Works - How-To Geek:

https://www.howtogeek.com/217043/xprotect-explained-how-your-macs-built-in-anti-malware-works/

Effective Defenses Against Malware (John Galt)- Apple Community

https://discussions.apple.com/thread/250921851

See this discussion from two years ago.