Unless the owner or the landlord permits it normally you can not make any permanent structural changes. A drop ceiling would be that. What is the issue with the current ceiling?

It has a descent lighting. I like bold colors. and this is a living room still in construction. The room has rectangular shape, this is half of the room. There is window on the opposite side of the TV(my back side while taking the above picture). The window size is 6 x 4 feet.

Hello Meghna, Do you have any pics of the room. Please let us know your preferred shades. Thanks, Nitin CORNERSTONE DESIGNS Bangalore

Hi Sheeba, Your could opt for wallpaper or cladding or texture walls or paneling as mentioned above. You could also consider putting frames around the TV, changing the light above the TV to a beautiful wall light and adding a plant (real or artificial) in the corner. This is an option if you don't want to spend too much money and want a simpler DIY solution. You could also upgrade your TV unit. Here's an example! Best Reema CUBSpaces Team