the first one is actually quite good it's got background and foreground elements just the rock at the bottom seems to look constrained in the framing i would of shot that scene slightly wider so the rock has a comfortable buffer between the bottom left edge
last one is good too it shows scale, but a good test for how much scale you should show is to reduce that image by 50% if the chair becomes so small it's unrecognisable it probably means its too small, you could re-crop that image tighter so the chair is slightly bigger in your comp
One easy trick is to shoot wide with a 12mm or nearest equivallent lens, everything looks super spatial at that range I use the nikon 12-24 and at 12mm the lens distorts landscapes in a way that makes them ultra spatial
here is what 12mm does
its almost a cheat, ive shot the same scene at 24mm doesn't look special
so make sure you work on your basics first, composition, tone etc
then snap it with a 12mm lens and your sweet
in terms of composition you can use off balanced composition
to lead the eye and 12 trick to make the scene more interesting is to use foreground elements this allows a nice visual interplay between foreground and background and shows relational scale
nothing wrong with placing an object neatly in the middle but sometimes a variation on obvious composition is more desireable
also helps if there are leading lines present that at least one leading line ends at one of the corners of the frame
anyway best thing is to keep on shooting and experimenting you'll get the hang of it in no time trust your visual judgement, landscape photography can be formulaic but it can also be stylistic so there are no rules.