good to see your enjoying your photography , the three images show your improving all the time
ive forgotten if you have manual settings on your camera or not , if you do its really easy to improve the shots
first shot there is plenty of drama in the sky , i love stormy cloudy days , try adding an adjustment layer and darkening the sky with a little more contrast see how it goes
second shot , maybe again some more contrast in the rocks but that is just my taste but worth trying , the sky is what is called blown out meaning its white with no detail ( overexposed) , you can fix this in photoshop by dropping a new sky in , but since your learning photography we should talk about fixing as best as possible in camera without getting into to much detail which may confuse , lets do a simple trick which i use for high contrast images often seen with bright skies and darker foregrounds , i do what we call bracketing , my camera will do it for me if i select bracketing so it will take 3 to 5 shots with the one click all at different exposures then i mask the areas i want in photoshop to create a nicer looking image with full detail
if you dont have a camera with bracketing option which im pretty sure you dont, then if you have manual settings you can take 3-5 pictures of the same scene with different exposures , so in your case with the second image i would simply take four more pictures doubling the shutter speed each time so that it got darker and the sky came back , then you could use layers in photoshop to join all the parts of the images together to get full detail
its best to do this on a tripod so the scene over the multiple shots doesnt change , some scenes its impossible to get all the image detail from the darks and lights with one exposure which is why we bracket at times
image number three , well done , i like it , if i were to critique i would say you would need the top of the house and chimney so you have a nice triangle drawing your eye , this would mean you would get a little more of the nice blue sky and less of the ugly concrete , id also either move for real if possible or clone out the chair at bottom left , this is a distracting part of the image to me , i would also have moved to the left a bit and pan a little more right so the house is on a straighter angle and you would then pick up the full unicorn sign and tilt the camera a little left as well so the bottom of the door is straight ( if you have some sort of grid in your viewfinder this helps keeping things level i use mine a lot especially for horizons , these are the things you will start to see more naturally before you take the shot as you become more experienced , remember to really study the scene before you shoot , ask yourself what is the subject in this case the house , ask yourself what will distract the viewer from the subject , and ask yourself am i getting the areas of interest i want and remember to look further into the image and see if there are tighter pictures that may work , so in this case maybe a close up of the flowers , maybe a close up of the unicorn sign etc
oh and one more thing and im not saying you shouldnt do it but generally harsh sunlight like the house picture dont look as good as soft light so choose the time of day if you have that option , you might of been able to get this image at a different time of day with no harsh shadows on the ground added some fill flash if it were all shadow might of made it really pop
hope you get something from the critique and remember its not critisism its just possibly pointing out how to take your photography to the next level