GIMP is a freeware photo editing/digital painting software.
http://www.gimp.org/
PSE stands for Photoshop Elements. However I think starting with GIMP is fine, since it is a program you don't have to pay to use.
What I would really recommend is drawing more with pencils before worrying about digital art, though. A house needs a good foundation, and so does your artwork. A lot of people jump right into digital art these days, and that's not horrible... but you can't very much drag your laptop around with you all the time. It's much nicer to capture things with a sketchbook and pencil during your day to day activities, in my opinion.
There isn't much I can gather from that one example, but everyone needs to draw from life to improve so it applies to you too. I think you should use more references, and practice gesture drawing. If you're interested in drawing animals, there are loads of resources online and pretty much everywhere.
Draw quick 30 second-1minute drawings from references. Don't worry about quality, this is about practice and learning how to draw fast without worrying about the results. The point of gesture drawing is to quickly put down the form and pose of whatever you're drawing. This is just my idea on things, but through my experience I noticed a lot of improvement when I started gesture drawing.
If you have any specific questions or I need to elaborate, don't be afraid to ask. My most important piece of advice is don't give up, and enjoy it!
Another thing, you are not a "drawer". People do not keep their clothes stuffed in you. You're an artist who renders in pencil/paint/whatever your medium is.