Decorate around it? In what way? Not with plants obviously, since it’s used to access the deck and the yard.

I actually want to discourage the use of the side and use only the front as the entrance way.

The last bottom "step"/tread should be a landing and that landing should be FLUSH with the grade .... not sitting 6" above it. The solution is to add topsoil around the landing to raise the grade so that it is flush with its surrounding, if this can be done without causing drainage problems. Or, add one more tread/"step" below and surrounding the current "landing," in order to make a landing that is flush with grade (without raising the grade.) But the idea of planting/"decorating" around this landing is flawed. No clues are given in the picture about why you would want to prevent anyone from stepping off the side onto what is obviously lawn. That warrants further explanation.

Personally, I'd want to get some fine gravel or similar to bring the level up to the step, then maybe you could put some small plants near it/in it if you want a garden, hostas, ferns, bleeding heart et al as it's in shade.

What holds the gravel in place?

What holds any garden in place?

I guess you could mosaic-tile it. Both the walking surface and the exposed sides (if you leave the sides exposed, that is).

Gravel would need a retainer edge. The end result is that the present landing would be larger (enlarged by gravel) but the problem has not gone away.

Looks like the OP not only needs the landing area in front of the concrete but a walkway to the steps. The walkway will lead to the front of the steps and generally keep people from the side. If there is no walkway, people will trample all over the area. JMO