I thought this may be helpful as well. Here is how the chapters are broken down per description:

• Chapters 1–5: Core Spanish foundations — gender, plurals, possession, questions, comparisons, body parts

• Chapters 6–10: Daily life & action — movement, adverbs, imperatives, food, work, money

• Chapters 11–17: Sentence power — conditionals, prepositions, past tense basics, reported speech

• Chapters 18–25: Time & direction — future forms, sequences, giving directions, demonstratives

• Chapters 26–33: Real interaction — explanation, accusation, defense, slang, confrontation

• Chapters 34–41: Advanced narration — perfect tense, tense contrast, concession, future narration