Q: I just bought a new Magic Mouse 2 but it cant not scroll.

You must be meet these requirements: Bluetooth-enabled Mac computer with OS X v10.11 or later.

You need to upgrade to El Capitan.   If your machine cannot go that far you will need to look at Amazon, where you may be able to get an older magic mouse version 1.    It does say on the box that you need version 10.11, but it is tiny writing.