Looks like you may already have a little bit of color blocking going on, but I'd increase the contrast between the shades of paint. Do you have access to the original paint chip card? Paint two of the walls in question in two different shades from that same card. Consult with the paint source for the complimentary color to accent the third wall. I think the middle wall to the right of the stairs would be the one I'd accent. Then add a large piece of colorful abstract art to that wall. Here's a quick tutorial on color blocking. https://www.houzz.com/magazine/building-with-blocks-of-color-stsetivw-vs~639

If furniture is all against walls a room will tend to have a flat, square, uninviting appearance. Even when placing a sofa "on the wall" you would want 3" inches space so the sofa won't rub the wall. The important thing is that furniture groupings facilitate conversation. Try moving your sofa out from the wall, if you don't like it, you can always move it back. :D Best wishes!

here is the layout of bedroom. the accent Wall has light shade than other walls. the floor has a beige color. please suggest something regarding furniture arrangement, decor that could fit a low budget.

A tricky question! Wall to wall carpeting is not a good option in India due to our hot climate as they tend to radiate heat and makes the rooms hotter. That said, they do add an aesthetic appeal and a decor feature when used in the living area. The choice rests with the individual.