The by Raymond Murphy is widely considered the "gold standard" for beginner to intermediate (A1–B1) English learners. Unlike thick, intimidating textbooks, this one uses a unique two-page format : the grammar rule on the left page, and practical exercises on the right.
To get the most out of your study sessions, don't just listen passively. Try these three techniques: The "Shadowing" Technique Basic Grammar In Use 4th Audio