You cannot create questions for Interviews when you are logged in to an interview session. However, you can access all your questions from the HackerRank library. So, all the questions created by you, your team, or HackerRank are available for your use in Interviews.
Interviews use the same questions available for tests. So, you can add questions to your personal library in your HackerRank for Work account that you want to use in Interviews.
Refer to the Create a new question topic to learn more about creating questions for HackerRank for Work account.