There is a wealth of guidance available online for the various different virtual meeting platforms and software, the links and videos below are just a small sample focussed on how to get started with using them. Further guidance on additional functionality of each one can be found on those pages in different sections.
One function you may wish to utilise, and most platforms do have the capability, is to share your screen with those you are meeting with. This can be very useful to enable you and the appraisee to see a document or web page you are looking it, and agree any comments being written or to confirm which entry to discuss. We do advise that you only use the share screen facility for short periods though and return to face to face virtual interaction when the necessary areas have been discussed/agreed. Guidance links have been included for screen sharing tutorials on each platform/software.
Platforms used predominantly on mobile devices such as WhatsApp, FaceTime and Google Duo do not appear to have screen sharing functionality.