not sur if you can plug an external gpu in your dell laptop i am googling it for you here and its not looking good
Are we talking a normal GPU inside of an external GPU enclosure? You can just pull the GPU out of its case and replace the card inside of it with that one.
Oh lol oops, didn't see it.
Well, most external GPU's need Thunderbolt to work, so if it doesn't have Thunderbolt that's connected through PCI-e your better off using internal graphics