Organizing child decks within a parent deck


I am trying to organize my decks on Anki so that all the cards that I have on there are organized into one parent deck instead of organized into subdecks. I specifically uploaded my card decks from Quizlet into Anki, but I am not sure how to put them into one deck so that all the cards are randomized. Whenever I click on the parent deck to see new cards, I get the first ones of the first child deck, then it continues based on whichever subdeck is next.

For example, if I click on “MCAT Quizlet: nkviswan”, it will start with Chapter 10: Social Thinking and go through all the cards, then will continue through the rest of the cards. Once all those cards are through, it will go into “Chapter 11: social structure and demographics” and so forth. Is there a way to randomize these cards so that they’re all jumbled into one deck that I can click on and see cards from any topic within the parent deck? Or is there a way to put/upload all the cards I make into a parent deck that will randomize it for me?

Thanks in advance!

You can try the new V3 scheduler, which supports this. See The 2021 scheduler - Frequently Asked Questions

Another option is to use filtered decks.

If you always study from the parent deck, you may want to consider using tags instead of subdecks to organize your notes into categories. See Adding/Editing - Anki Manual