I have ADHD as well, so I know your struggle. You should check out The Worldview and Philosophical Methodology of Marxism-Leninism: Curriculum of the Basic Principles of Marxism-Leninism Part 1. It is a free book. You can buy the E-Book for $0 on their site

From the Preface:

The text of this book constitutes part one of a four-part curriculum on Marxism-Leninism developed and published by the Ministry of Education and Training of Vietnam. This curriculum is intended for students who are not specializing in the study of Marxism-Leninism, and is intended to give every Vietnamese student a firm grounding in the political philosophy of scientific socialism.

The entire curriculum consists of:

Part 1: Dialectical Materialism (this text)

Part 2: Historical Materialism

Part 3: Political Economy

Part 4: Scientific Socialism

In Vietnam, each part of the curriculum encompasses one full semester of mandatory study for all college students. Each part builds upon the previous, meaning that this text is the foundation for all political theory education for most college students in Vietnam.

However, it is important to note that this is not the first encounter with dialectical materialism which Vietnamese students wil have had with these ideas, because Vietnamese students also study dialectical materialism, historical materialism, political economy, and scientific socialism from primary school all the way through high school.

As such, the text of this book - in and of itself - would probably seem overwhelmingly condensed to most foreign readers who are new to studying dialectical materialism. Therefore, we have decided to extensively annotate and illustrate this text with the information which would have been previously obtained in a basic Vietnamese high school education and/or provided by college lecturers in the classroom.

This book covers the following:

• Introduction to the Basic Principles of Marxism-Leninism
  • I. Brief History of Marxism-Leninism
  • II. Objects, Purposes and Requirements for Studying the Basic Principles of Marxism-Leninism
• Part I: The Worldview and Philosophical Methodology of Marxism-Leninism
  • Chapter I: Dialectical Materialism
    • I. Materialism and Dialectical Materialism
    • II. Dialectical Materialist Opinions About Matter, Consciousness, and the Relationship Between Matter and Consciousness
  • Chapter 2: Materialist Dialectics
    • I. Dialectics and Materialist Dialectics
    • II. Basic Principles of Materialist Dialectics
    • III. Basic Pairs of Categories of Materialist Dialectics
    • IV. Baisc Laws of Materialist Dialectics
  • Chapter 3: Cognitive Theory of Dialectical Materialism
    • 1. Praxis, Consciousness and the Role of Praxis in Consciousness
    • 2. Dialectical Path of Consciousness to Truth

I found this book to be incredibly useful for laying the foundation of my understanding of Marxism-Leninism. It synthesizes all the theoretical work spread across many of the writings of Marx, Engels and Lenin into a single volume. It contains a glossary of terms as well, which is very useful as a study tool. I think it should be required reading for all comrades. I should probably give it another read.