If you've still got a legacy voice system, meaning an on-site PBX with analog phones, then your only real COVID response will be call forwarding to your employees' home phones. That may or may not be acceptable to your employees, especially since these days many of them won't have an analog phone available, which means you'll need to do your forwarding to a personally-owned mobile phone.
For locations where a desk phone is required but no Ethernet cable is nearby, Yealink offers an option to use it’s reliable and secure DECT wireless extender or you can use your Wi-Fi if you prefer for quick and easy desk phone placement in places where no Ethernet cable is easily accessible — an ideal solution for installations that simply cannot run new Cat6 cabling everywhere.

A virtual phone number is a telephone number without a phone line directly associated with it. Instead of being connected to one specific telephone line, a virtual number is programmed to forward incoming calls to one of the pre-set telephone lines that the client chooses, be it fixed, mobile or VoIP. Virtual phone numbers are also known as access numbers since they can work as a gateway between traditional calls and VoIP.
On top of that, they're often expected to provide more advanced functionality through software, like shared meeting collaboration, voicemail to email transcription, and call recording. And lest we forget, many businesses still need a service that will connect to the public switched telephone network (PSTN).