That specification is asking you to use the display property with a value of grid to apply styling to that part of your HTML page. I would recommend reviewing the lesson on CSS Layout to review the display property, and then check out this documentation to see some examples of grid layout and how it is used in your CSS code.
Specifically for this assessment, you will want to use the grid layout for all of the labels and all of the form elements when the screen is greater than or equal to 600px wide.
Take a look at these resources, and let us know what you think!
Jesse