Welcome to the site. I'm glad that you are seeking advice before you made an ill advised purchase or treated a plant inappropriately. One of the very first things you should be aware of is that unless you intend to grow tropicals/sub-tropicals bonsai is an outside activity. This implies that your adventure probably won't begin until next spring.
Next, I don't think it is a particularly good idea for beginners to grow from seed/cuttings, at least not exclusively so. Such small stock can take years/decades before you have anything to work with. Similarly, many but not all, mass produced bonsai are so young that it will be quite some time before anything substantial will be achieved. There are other methods of acquiring bonsai that will get you off to a quicker start.
A much better approach is to purchase something a little more advanced from a specialized nursery. Another option is to visit a conventional nursery and spend some time poking around the grounds. You can create your own bonsai from nursery stock and learn something in the process. If you have experience with trees/plants in general, excellent material can be collected from the urban landscape. Keep your eye out next spring for neighbors removing old landscape material.
Most of all, read everything you can get your hands on. Visit your local library and see what they have. Be aware though that some books you find there may be a bit dated on certain subjects, soil comes to mind. Today most growers use a mix that is composed primarily of inorganic ingredients with fired clay and lava rock being two of the most common. No actual soil in any of my bonsai/training pots. I believe that there is a thread with suggestions for book to read/purchase, use the search feature at the top of the page.
Here are some links that should answer many of your initial questions.
I know I have only scratched the surface and others will probably have more to add. Good luck and don't hesitate to ask more questions as they arise.