Please refer to page 22 of
the instruction manual. You print out transcript request forms for each of the institutions you attended, which are passed on to the registrars at those institutions when you request transcripts. The specific mechanism by which you do so is school-specific.
You can send your transcripts before you have submitted your application. You must have started an application, of course.
No. They are not processing transcripts. They are processing your application, in which you enter your grades. The transcripts are used to confirm that you have entered them correctly and to make changes as needed.
As Renaissance Man indicated, these questions have already been answered. Your first step should always be to consult the sticked thread at the top of the forum when you have any questions about the process.