Edit fields IPTC:Caption-Abstract or XMP:Description

Is there a way in Lightroom to edit the fields IPTC:Caption-Abstract or XMP:Description?

Ideally I'd like those fields to be editable in the Info pane (see my screenshot below). I'm new to Lightroom and I'm using the desktop version for MacBook, which I believe is different from Lightroom Classic, but I'm not sure.  

I'm trying to edit those fields because I believe when I then import to Google Photos, the edits will appear in Google Photos' description field.