Right click on that item and then choose create shortcut and after that a dialogue box will appear, in that click browse and set desired location to desktop and then your shortcut will be created.
Right click that item and choose delete and it will move to recyble bin. If you want to permanently remove an item press " shift + delete" , it will be removed permanently from your desktop.
First check the kind of processor you are using and is it compatible to support more RAM. There are are two types RAM available DDR3 and DDR4, check which one your PC supports.After that you can upgrade your PC and also check whether your PC has two RAM slots or not.