Making a depth perception simulator, newbie programmer

HI

I need to make a program for University, where there's different conditions where objects are placed at different defined lengths like 0,1 m, 1 m and stuff like that. And then the condition needs to change if the testsubject answers how far away the object is or two minutes have passed.
Does anyone have an idea for how to execute it? Any advice is welcomed with open armes.

Love Christina