Can anyone recommend me a really good tutorial for learning Joomla, most of which I found were spam ads just to get people to click several ads without learning anything. I'm using Joomla for the first time and I'm sort of confused with certain terms because they are all alike.
For example, Section and Category almost same, and so on.
Maybe joomla is not the right choice for me, what I really need is some kind of CMS that is:
The best tutorial you can get is to install Joomla on your localhost and just play around with it!
Besides Joomla you can also look into other CMS but I'd say Joomla fits best to the criteria you mentioned. Wordpress was originally a blogging engine and that's what is still mostly is. Drupal is another great free PHP CMS but if you want ease-of-use then Joomla wins over Drupal. Both have loads of extensions but also there Joomla wins. At least in terms of quantity... quality is another question. In the Joomla extension universe, the quality can be from incredibly bad to excellent. With drupal the variance is a bit smaller, I'd say.
Whether or not your Joomla install gets hacked really depends mostly on how you host it. Example: Most ppl use JoomlaPack with Joomla but they use the default settings which means the backup directory is inside the web root. And that can be a security problem.
maybe you find http://www.joomlatutorials.com/ helpful, you'll find there a lot of information concerning changing templates, understanding the admin backend, playing around with menu manager an so on. hope that helps
Try the Joomla beginner's guide for help. Personally I have found Joomla quite easy to use, you can do what you said above (adding articles and so on) quite simply.
Regarding the part about sections/categories: categories are basically sub-sections. So you might have sections like 'Sports' and 'Technology' with categories like 'Baseball' or 'Football' for sports, and 'Windows' or 'Mac' for technology.