what file (name and extension) are you using to install pre?
You don't "change" what you have... you go back to the link you used for your download and download the 64bit installer
What computer operating system are you trying to download Premiere Elements to? And, where is the download coming from, Adobe or other?
Are you trying to download a tryout of Premiere Elements 12 or have you purchased with serial number an online download of Premiere Elements 12 from Adobe?
When you are given download files, there should be 2, what are the file names? I would expect the first should have a file extension of .exe and the second should have a file extension of .7z. Is there a 32 or 64 in the file name in either of these files?
The answers will be in your details and will include obtaining the correct installation files for Premiere Elements 12 from the source as mentioned. But that is easier said than done. So I am emphasizing the details that brought you to where you are so that you will see more clearly how to work yourself to success.
Looking forward to learning of your progress and success.