Your best bet is to download from the vendor's official Web site at this link.
Please let me know what operating system you have, and I can offer more detailed assistance.
I apologize, but I know nothing about the site's pricing policies. Would you like to try following some simple directions first? I understand that you say you are a novice, but, if you just try to install it, you will develop confidence for the next time. I promise you it will not be complicated. Thank you for your understanding.
O.K., based upon what you've told me so far, please click ON THIS LINK and obey the download instructions as best you can. Chrome will display a progress bar in the lower left corner of the window. I'm trying it on my machine so I can give you very complete instructions. WARNING: even at top speed, it is EXTREMELY SLOW to download. Please stand by.
Click the little arrow at the right side of the "downloading" information box and choose "open when done." It will automatically open and prompt you to run the .EXE to install the software. From this point the instructions should be very much self-explanatory.