The easy answer is "click Attach in the issue to which you want to upload the file to".
But I suspect you are asking something less technical. Are your renenewals supposed to be issues for people to work with? New or updated? Should it really be a simple attachment on an existing issue? Or should you be creating a new issue?
Most of the questions go back to "why"? What are you trying to do, and who told you to do it that way, and why that way?