Follow the below steps to add a pre-defined question paper to a test:

Click on the "Add Question Paper" option in the round where you want to add the question paper.

To search the pre-defined question paper, enter the details in the filter panel such as skill tag, difficulty level, question type.

To choose the question paper from the available list, click on the question paper to preview its summary.

Click on the "Use This Test" option to add the question paper to the test.