I started out with opencanvas 1.1 and a mouse. Opencanvas 1.1 is completely free to download, though I'm sure there are plenty of other free painting software available now. I looked through a lot of tutorials on deviantart. There are a ton here, and even if they're using the latest Photoshop, they are still useful. After a while I got a tablet and then upgraded to opencanvas 4. I'm currently using Corel Painter X, but that learning curve took a while for me to push through. Draw and paint from observation - this goes for traditional media, too. Use photo references and draw objects sitting around you. A lot of learning how to use any medium is looking at what other people are doing and how they do it, working from references and really observing and processing what things look like, and then just drawing every day and trying to push yourself. But an important thing to keep in mind is to not blame your materials. Using high-end media or programs will not automatically improve your artwork. Start with simpler tools, master those first. You have pencils - work with those! You can do /amazing/ things with graphite. And don't get discouraged. Be self critical, seek constructive criticism, and then learn how to improve and grow from that!
I didn't go to art school, and I don't know much about them. But you do need a portfolio in order to apply. For me, the art classes I took did not hold my hand through figuring out the media. They were great for pushing me outside of my comfort zone, learning how to objectively critique myself, and problem solving. But I already had to know a little about what I was doing first.