Drawing Element inside of Perspective - where to find?

[witman]

You're not missing anything. Perspective doesn't have drawing tools--though they are planned.

[BUG-11342] Perspective - Can't draw any shapes

Interactive drawing tools will be added to Perspective, absolutely. I doubt they’ll make the initial 8.0 release, however. That said, support for vector drawings (svg) is in perspective today. You can draw something (in inkscape, for example), save it as an SVG, and then drag it into perspective. You will notice that the properties of the drawing component that is created actually contains all of the SVG paths, transforms, styles, etc. So while it is certainly awkward and inconvenient to do so …

For now, you can import SVGs drawn in other programs. Search "Perspective drawing" on this forum and you'll find some tips.