How to correctly define semantics through BEM?

Question

HTML

Hello everyone, I'm sitting here studying BEM and decided to make a website right away. The site consists of the first block where the parallax elements will be located and the second. The second one appears when scrolling there is just text, pictures, etc.
The question is whether BEM was used correctly in this case. What does -- mean? And when should modifiers be used? Is it necessary to use prefixes or is it better without them, as practice shows?

<div class="b-popup"></div>
  <div class="b-main">
    <div class="b-main-scroll"></div>
    <div class="b-main-content">
      <div class="b-car">
        <div class="b-car__item"></div>
      </div>
      <div class="b_footer"></div>
    </div>
  </div>

Answer 1

Practice shows - do not use BEM. For only its developers know all their subtleties, and according to rumors, Yandex itself goes to Stylus.

Answer 2

No way. BEM is needed only to simplify the process of changing the layout in the case of automatic content generation (and, accordingly, automatic generation of class names in the BEM hierarchy). To prescribe all these monstrous parodies of names with your hands is a monkey's work.

Answer 3

Here it is the result of recommendations to study BEM for everyone and beginners too.

Answer 4

Use bem-naming .