What should a layperson do who finds it difficult to understand some Arabic words when reading religious books, such as commentaries on the books of Muhammad ibn Abd al-Wahhab, and are there books for learning the Arabic language that can help with that?

A student of knowledge should consult scholars regarding the choice of books to read and seek their help with anything difficult to understand, as learning through direct oral transmission is the primary method. If this is not possible, then one should consult scholars about the books they read. The book "Kitab al-Tawhid" by Sheikh Muhammad ibn Abd al-Wahhab is considered among the important books, and among its accessible commentaries are those by Sheikh Salih Aal al-Sheikh and Sheikh Abd al-Rahman al-Sa'di. As for books on learning the Arabic language, they are many and readily available, and among the most important Arabic dictionaries is "Al-Mu'jam al-Wasit."