1)
To add apps to a screen you can either go to the apps drawer and long press the the app OR you can long press the screen you want to add to and you will have the option to either add Widgets, Apps, or Shortcuts.
2)
To move apps around once they are on your screen just long press the app where you would like it to go ... If you want them on a different screen just slide them to the edge of the screen to move between the left and right screens.
3)
To remove apps from screen, long press the app and slide it to the upper right hand corner marked "remove".
4)
To QUICKLY unistall an app, go to app drawer ... Long press on the app ... Then drag to the upper left marked "uninstall".