1/2000s f/6.3 at 400.0mm iso200
That indicates the shot was taken at a shutter speed of 1/2000 of a second, the aperture (opening within the lens, which is variable) was f/6.3. That means the diameter of the opening was approximately 63mm (400 / 6.3). The focal length of the lens is 400mm, which I believe is a "prime" (i.e., non-zoom) lens. The "film speed" (or more accurately, the sensor sensitivity to light) was set to ISO200, which is also variable on most "non point-and-shoot" cameras.
Now, as to what all that implies is a bit beyond the scope of this message
, but an oft recommended book is "Understanding Exposure" by Bryan Peterson. There are a number of decent tutorials on the web, as to be expected.
I don't know "where you're at" in your photographic journey (geez, that sounded corny!), but on a very fundamental level...
Shutter speed - Faster captures motion; slower blurs it
Aperture - "Faster", i.e., larger numbers, larger openings blurs the background; smaller apertures give greater depth of field, i.e., more is in focus on either side of the focal point.
ISO speed - Larger (faster) is more sensitive to light and therefore can be used in lower light situations.
These are the big three that balance against each other to provide variances within the limits of a "properly exposed" image. Once you learn what causes what variances and what you want in regard to them, you're well on your way. There are, of course, trade-offs for everything I've listed above, just to keep you from getting too comfortable!