Anki flashcards are a learning aid based on spaced recognition. I have been using these for my cloud studies
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I create a deck for each subject: AWS, GCP. etc. On the front of th ecard I put the questions and the answer goes on the back of the cards. I also assign a tag sych as storage, compute. network . etc.
When running in study mode it displays the questions and you answer verbally, and then self-rate your response. This system will replay questions sooner if you for low ratings and later for high ratings. In this way it allows you to focus your learnings of your weak areas until you havegood all round performance