Let's take a look at creating the different question types.
Fill In the Blanks
Select "Fill in the Blanks"
Select the question text box and then select the "Insert fill in the blank input" icon on the right side of the box that appears.
Then insert your question text into the question text box and then your answer into the "Answer(s)" box that appears below
Once complete, select the tick mark on the bottom right to save!