You have to write the questions (and answers) manually. When you hit create a quiz, and after you enter the quiz information (it is recommended that you guard it with a password if you want to earn credits off of it)(it's also recommended strongly that you limit the number of attempts to 1, and turn adaptive mode OFF) you should see the added questions on the left and your question bank on the right.
To create a question, choose the question type from the "Add a question" section on the right, and enter all of the question info. It should appear in your question bank. Just take it from there and add it to your quiz.
I know it seems confusing, but it becomes easy after the first time

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