Can annotations remain on the screen?

I've just started using RingCentral after migrating from Zoom, and the biggest let-down is the annotations - all I can do is make a mark that disappears after a few seconds. As someone who sometimes uses these calls to teach, I'd often like to write in text to annotate a page, or to draw lines and have them remain on the page. Is this really all that's available, or am I missing something? Thanks!