there is a fireplace behind the door so I don't think white color will be a good choice to me.Also do you prefer fabric curtain or roll curtain?

I have moved to a new house and there are difference in sizes,so I am wondering also about the empty corner how can I fill it?

My first thought was "mustard or navy." My second thought was "match the walls," but the wall color actually looks pretty bad with the sofa. My third thought was a cream like the rose in the upholstery, but I think that would also look pretty bad with the current will paint.

Can you/would you be willing to paint? I think a cream like the color of the rose is the upholstery would flatter the sofa much more than the current wall color. If you did that, then curtains that match the walls would be nice.

If you can't/won't paint, then I think maybe navy would work best. Navy works better with the paint than the mustard.

I'm not sure what you mean by a "roll curtain" unless you really mean blinds or shades and not curtains. Sliding doors don't work particularly well with anything that pulls down from the top, so you either want a curtain you can pull to the side or vertical blinds that pull to the side. Vertical blinds are out of fashion.

For the corner, something taller than the back of the sofa. A floor lamp, a tall potted plant, or a bookshelf would provide visual interest.

What about a blue curtain (the same color as the lightest blue in your rug) and a floor lamp for the corner?

That's a really cool and unusual sofa! I'd do something plain and pick up the beige from the roses in the center of the sofa pillows. Something neutral, maybe a bit rustic looking like muslin. As for the corner, I'd have a bookshelf and art, but that's only because I have bookshelves and art in almost every blank wall space in my house . . .

thanks for your time. honestly I am not willing to paint for now. the Navy color it won't make the room darker?! and yes I meant about "roll" blinds and shades, so I won't put them as ur advice.
will bateau curtain be a good choice?
and what about the fabric? velvet as the sofa?

as for the third advice, yes it's unusual and hard to complete the room based on that color (its not a yellow mustard more green),I feel its empty and need something on the wall or the rug doesn't fit well.
for the muslin color(is it muslin in the rose?!) I will try a sample.
if I want to get poofs which color will I choose?
and about the cushions will it look bad if I get some or it doesn't need?
Thank you

The rug is OK and I am loathe to tell someone to spend extra money when they just asked about curtains, but if you have an alternate spot for the rug or don't mind donating it to charity or something, I think you could do better with a different rug. The rug you have is nice, but very geometric and a whole different color palette than the couch. They kind of fight for dominance in the room. You might be able to find a rug that plays nicer with your couch, in terms of color and design. Maybe just work on the curtains, not worry too much about the rug, but then after you get the curtains, keep your eyes out for a better rug that "ties the room together." (Esoteric movie reference from "The Big Lebowski.") Use the floral design from the couch as your color palette when making choices for the room. Don't worry about the walls, they are pale enough to fade into the background once you get the curtains and some art up on the walls.

thanks all for ur advice,I will keep the rug for now and for the curtains I am still confused about the color there are several options and I am not sure which mostly fit. for the navy and mustard color I am afraid to make my room darker (which is not a living room,a corner in the kitchen). and for the muslin color do u mean a flower texture in the curtain or untextured? and what about the fabric type? will I keep on velvet? What's about a light blue as the flowers in the sofa.will it be nice? Thanks for ur time :)

I think a lighter curtain color would be better, but some others have suggested a darker color. I don't think there is a right or wrong answer, just depends on the look you are seeking. A bold color won't necessarily make the room look darker, but heavy thick material for the curtains, or if they're lined, will. I guess that's why I said "muslin" which is a thinner fabric with a loose weave. That's what I'm thinking of, but it doesn't have to be muslin per se. I think a darker color in a velvet type material would be very dramatic. Depends on if you want to be dramatic, lol! As long as you keep the drapes open, should not affect the light in the room that much.

Whether navy will be too dark depends on whether you expect to keep the curtains mostly open or mostly shut. If mostly open, I think navy is fine.

Seeing the close up of the fabric, the lighter blue might be a nice choice as well.

what do u think between these colors it's a linen fabric, and organza.will it be nice if I put organza with a blackout or use the coton type!
eylet or rod pocket style?

I like the light teal color (5th from the bottom in your last picture), pocket style.

I think shade of purplish-blue or Chocolate brown color curtains will coordinate well with mustard and navy blue sofa if you want to give a elegant look to your room.

Blush pink would go beautiful

I think any of your samples would work fine.

That is one amazing couch! Is it vintage? I love it!