When you install a new app it installs it in the last open space on the home page. If the last spot on the home page is filled, it will install the icon after all other apps. It won't put it in the first open spot. If this means creating a new page it will.
Long press the home screen until you get the wallpaper and widget options
You'll see the outlines for the home screens. On the top is a home icon, put the screen you want underneath that icon, then tap. It should whiten the border of the screen you pick, and that will be the screen the apps go to