How to start with tracking & viewing specific actions per page?

Hi guys,

So I started a couple of days ago with piwik with the idea to track multiple actions per page.
Now I don’t know how to track how many people clicked a single button, which does not redirect to a new page.
I also want it to be possible to give users acces to specific pages.
Is there any way to make this possible?
How do I start with this?

I’ve already looked at the custom dimensions and the custom variables but I don’t think I can use them for what I want.

Thanks in advance!!

Tim