I am in total manual mode here, and that as a copy of the exif so im pretty sure its 100.
Ah I figured that this lense could be good for this type of picture

. However it sounds like it was the big culprit here. I can try with those settings though.
Several points need to be clarified. You've got an 18-135mm f/3.5 lens that you are using at 1) maximum aperture and 2) its widest focal length. A few things about that...
If you stop down the lens will be sharper. Maybe f/5.6 or f/6.3, though f/8 would be okay but f/11 is asking for diffraction. Even at f/8 you will not gain depth of field! With it set to 18mm focal length, at f/3.5 the hyperfocal distance is 4.88 meters. That means if you were actually focused on any object farther than about 16 feet from you,
everything out to infinity will be in focus. Given that scene, where you can't even see anything within much closer than 16 feet to focus on, depth of field means exactly nothing!
You might get something just a hair sharper by using a slightly longer focal length. It might not be enough to notice.
Your image is not underexpose by any definition. It is
overexposed because every highlight in the image is clipping! As it is, you probably don't care about most highlights clipping, and as long as nothing blooms from excess exposure it will be okay. However, given that it is possible with that image to pull the shadows up by at least a couple stops (getting color and detail in leaves of the tree in the lower center foreground), reducing the exposure by 1 or even 2 stops would not hurt a thing.
I don't have data for the Canon 650D, but unless it is radically different than other Canon sensor you might actually be a little better off at ISO 200, and you certainly won't suffer at ISO 400. With virtually any Canon sensor you can use ISO 800 and still have more dynamic range that will fit into a JPEG, but you'll have to process more carefully to ensure that.
The use of 0.8 seconds shutter speed is inviting vibration from the shutter to affect the image. That's about the worst possible shutter speed! If you have a good tripod, use mirror lockup at anything from about 1/10th of a second out maybe 5 seconds. Otherwise, avoid that range and use either a faster or slower shutter speed.