In my Canvas settings, I see that Quizzes.Next is On.
In Assignments, I selected +Quiz/Test (Beta).
I gave my Assignment a name, assigned points, and assigned it to a class (in this class a test class that I created).
Next, I selected Save (I've also tried Save & Publish).
This is what I see (on the left / I have extended screens).
I do not find a build option to create the questions.