If you're logged into this forum, you're using your valid Adobe ID. Just use the same ID to log into Adobe.com. You'll find the option to purchase the software on this page, at which point you'll be sent a serial number to activate your product.
Thank you. So do i use this serial number to plug it into thee window that popped out?
Yes. Type or paste the serial number into the boxes when you're prompted.
You have just started a new thread on the subject of buying Premiere Elements 13 and on problems with the suggestion given in this earlier thread today.
Your most recent thread on this matter can be found
I have added some comments there.
Basically I have suggested that you use the Adobe Chat Buy link on the web page that you were given in the thread that we are in now in order to have Adobe Chat Buy sort out the problems in its Buying process.