Is this good for better gaming experience?

Hi I'm having Hp Probook 4520s.it has 2Gb of ram,Intel i3 processor with 2Ghz and integrated Intel graphics.i found some games are being troubled to start.this system specifications is good for gaming?can i get good gaming after upgrading my ram memory to 4Gb or 8?is there any way to add a graphics card?please answer this three questions.ding my ram memory to 4Gb or 8?is there any way to add a graphics card?please answer this three questions.