Possible to convert an ER Diagram in QuickBase?

I didn't use an ER diagramming tool.  With one of my Gmail accounts I have access to a free add-on called draw.io.  It is a glorified version of doing a flowchart in Word, except it comes with database tables predrawn.  It's exactly like you do by hand only on the screen.  It doesn't help in any way by saying that a primary key is used twice or by helping to "see" the flow.  It's just a simple flowchart builder.  I do have Visio, but this is free and very easy.