During my work I use the books published by British publising house Speak Out - for adults. These books are divided according to the level of your language. They consist of a Student Book and a Workbook + audio materials. For teachers there is a Teacher's book with some additional materials. You can easily find them here https://www.english.com/speakout/
Also yu can use https://quizlet.com/ to study new vocabulary, for example my module https://quizlet.com/381347851/transport-adjectives-speakout-pearson-starter-flash-cards/