A good start is to read through the 'Terms and definitions' section of this FAQ section. Also the other FAQs will build up a good picture of what Xoops is about and how to understand many of the terms and concepts.
We also feature links to TRAINING RESOURCES
on the Documentation site. Most of these links are to reputable third party websites that offer free online information about all aspects of web-building.
Finally, always feel free to ask on the forums, or search the site for information you need to learn.