I think you really need to try and find a basic electronics course at you local college, or a night class. Using a multimeter is the most basic elements of this industry and if you dont know how to use one, and clearly you do not, you should not be doing any work at all in this industry. Not understanding how to take basic measurements in this industry is like wondering around a crowded tube station blindfolded, your gonna bump into something sooner or later, lets hope its not a tube train.
Honestly I wouldnt employ a trainee that doesnt have the basics, you would not pass our interview exam.
I am giving advice here not taking the P, get on a basic electronic course once you understand the fundamentals you will have a much better understanding of whats going on.
But asking us to teach you the basics is asking for trouble, because someone will rip the pss