Hi @kathygray68 ,

To render online start here:

https://gallery.autodesk.com/a360rendering

On the first page sign in to your Autodesk account:

At the top of the next page pick on NEW button:

Then select "Upload file and start rendering" link:

Then pick on "Select file" button:

 And upload drawing from your Mac to the Cloud.

For the next steps refer to Rendering online Help:

https://help.autodesk.com/view/ARENDERING/ENU/?guid=GUID-387E4CB4-CD53-48C9-BB1A-E7A243CF4383

HTH