It can be overwhelming at first. But its not so hard to get the hang of. On the upper left is an index. Click on that and you can see all the topics. Click on one that interests you and you will see the recent threads that fall under each topic. If you have a question select the closest topic and start a new thread with your question.
There is a FAQ section that can answer a lot of your questions about posting and navigating the site and the crazy abbreviations people use.