Hello reinelic,
I remember how much skull sweat learning regex cost me (both the first time in PERL, years ago, and now again for web dev). Here are the links I found helpful when learning them, especially regexr.
Quick table of regex operators
In-depth tutorial, looks very granularly at the regex engine, uses colors to illustrate concepts
To get you started on the path to regex mastery, here’s a regexr for the givens you’ve provided