The screen "Bezel" will come off and some Dell models can be a royal pain to get apart.(Plastic tabs after screw removal)... You need to be sure all Rubber style plugs on the "bezel" or Screen side are removed, Look to the thin outer edges for any other covers that may have hidden screws beneath and starting at the bottom is usually the best option for getting the ring or "Bezel" off.[Plastic ring in front when looking at screen]. Next thing to do is locate a hinge and I'd suggest contacting Dell parts for the components. You will also need to take 2-3 screws out on the bottom of the unit to release the plastic panel between the keyboard and screen assembly. (Hinges screw into the base).. Reverse process and all is well.

Notice how many times I state, "Bezel"