Choosing between a and de

Hello, I’ve really struggled with this lesson. I’ve finally figured out that it is the verb itself that decides whether or not you use ‘a’ or ‘de’. It just wasn’t clicking. So first I will start learning which preposition follows specific verbs, then I will come back to this. Your lesson is about learning that ‘a+el’ is ‘al’ and ‘de+el’ is ‘del’. And I understand that completely. I don’t recall if there is a lesson about correct propositions after verbs. Please let me know if there is. Thank you!