I have steps on each side of my couch and mine will use it sometimes and not others. I also have steps leading up to the cover on the hot tub and while they go up that, they usually will jumpover the top (3rd) step, lol. I would say give him time, and he will learn and get the hang of the steps.
Maybe try using a leash to walk him up and down the stairs to give him an idea of what you want him to do.
