You can speak English fluently without studying grammar rules
I am a native English speaker, majored in English Literature, and have been teaching English for more than 10 years. However, many of my students know more details about English grammar than I do. I can easily look up the definition and apply it, but I don't know it off the top of my head.
I often ask my native English friends some grammar questions, and only a few of them know the correct answer. However, they are fluent in English and can read, speak, listen, and communicate effectively.
Do you want to be able to recite the definition of a causative verb, or do you want to be able to speak English fluently?