HI -- The room is large enough to spread out a bit . Back a sofa /square sectional to the star wall to face the fireplace . Put the TV on the white bench wall with a console/buffet under . If you have the sectional with the short end on the left end of sofa section then a console/sofa table or desk can back that end and then have a couple of chairs at the front window . Then there could be a swivel chair off the right end of the sofa that can be turned for TV viewing .

PS: If you are keeping the sofa and chair you have then just switch their places. I made a correction in first comment about sofa facing the fireplace . I had said TV when it was supposed to be fireplace .

I see what you're saying, but then if you set in the couch (that's facing the fireplace) to watch TV, you have to turn your head 90 degrees to the left.

I agree with moving the sofa to face the fireplace. Place the chair with it's back to the kitchen and square with the sofa. Then place your TV on one of the walls to the right of the fireplace/steps.

I would put the TV opposite the fireplace, then have two sofas or a sofa and two chairs perpendicular to the fireplace facing each other.

That gives you a good sized area to the right of the stairs (which naturally divides the room anyway) which could be a desk area, or a small conversation area, or maybe have a game table...