Maybe walls and drop ceiling could be painted in a vibrant accent color instead of more beige. Stripes are usually formal, more casual if not the same size. Chic could be achieved with silver and beige stripes - wide and horizontal. Here is an idea book on stripes and one on how to DIY. https://www.houzz.com/magazine/the-case-for-striped-walls-stsetivw-vs~225887 https://www.houzz.com/magazine/how-to-paint-perfect-wall-stripes-stsetivw-vs~3427677

I have to set up my New Living cum Dining room. Drawing is as attached. I do not have a sofa and I do not plan to buy any. Instead, I will prefer to buy some light weight chairs. I already have a 6 seater Dining table, a single bed and 3 old trunks of my MIL which I plan to put somewhere in this room and cover up with some padding above it and a good bed cover or Table cover. Please suggest me a good idea.

I think I am certainly quite late to reply on this post but nevertheless will put my suggestions here. Go for 2 loveseats in a light/neutral colour against the 7 ft and 15 ft wall. Opposite the 15 ft wall you could put a nice upholstered bench in contrast/printed fabric. Also for a warm glow put a nice standing lamp in the corner between both sofas. You can place a nice mirror on the TV wall and put a nice shelf beneath it and place a lamp there with few knick knacks if the door opens outside in the balcony or is sliding. Also, keep two upholstered ottomans below the mirror which can be pulled for extra seating when required. Place a low height coffee table small one like a 2x2 ft.

For the dining room, I think I'd orient the table 90 degrees from how it's drawn, and I would make it a drop leaf or gateleg table so that it can be made smaller when not being used for dining. I would embrace the idea that the entry is right in the middle of the living room, and bring the living room furniture out towards the fireplace so the fireplace is connected to the seating area. Maybe TV above fireplace. In that back corner where the sofa is drawn, I'd make that a small work/office space.