Why can't I open Itunes on the other account on my computer?

I have Itunes downloaded onto my computer (windows 10), but I am only able to open itunes on the admin account. If I try to search it using the windows button on the second account then it only shows an internet search of itunes. It does not show the app. I've tried to download it using the apple store, but whenever I hit "Download Now" it takes me back to the home page of the apple store and downloads nothing.