If you are using a Mac, you may not see the new icon and may have to search for it in your file system.

(The General Instructions for this forum ask everyone to include what version of Finale and what operating system they are using when asking a question. Please do that.)

Just downloading it doesn't install it. You need to find it (look in your Downloads folder) and then you will have to decompress it and install it. Generally, you just double-click the icons to do that. Once it's installed, when you launch it for the first time, you will be asked for your serial number.

This worthless forum software doesn't have a place to enter your system specs, so, as JAV says, you need to write it in so we know how to answer you.