I can only see 80% of my monitor

Just trying to do what I've been told.  I have a screenshot below of my Device Manager Screen

I can see why you're struggling for info now, not exactly helpful from what can be seen, BUT, that said, I found a clue as to what you have, and with luck it is an Inspiron 1520 laptop ?

Assuming it is, click on the link and let their scanner run on your system (install the active x as needed), that way it will take you to the correct drivers for your system, as these are often varied among systems falling under the same badge, download the latest (they often show older drivers at the same time, so look at the dates they were released in the notes) Chipset, and Video\display drivers, then install them, and they should at least resolve the driver side of things.

If the device manager is showing no issues after doing this, and the problem still exists, I will dig into the manual if needed to see if there are mentions of adjusting a laptop screen size in the way I would a stand alone monitor, as I have never had to do that on a laptop (or even know if it can be done), but hopefully this helps a bit anyway.