Dynamic Drop down populate on basis of selection of another input

I would like to populate my one drop down on basis of another drop down.

For e.g. - I have two drop downs 1 - Shape, 2 - Properties

Mapping is like - Triangle : { Sides } Circle :{ diameter, radius }

When I select Triangle in the first option then in the second drop down sides should be available.

Can someone help with the openapi yaml configuration.