Oh, wow, 10 years ago! There is a special tool meant just for grout removal, your local hardware store should have it. It will be time consuming but aside from removing everything it's probably the way you'll need to go.

Sir you can use Wooden textured ACP as it will be cost effective solution to cover Soil pipes and provide a modern look to facade .

two basic issues your room floor is dull is that floor to floor carpet if yes then add a a smaller area rug under your table to get splash of colour, alternatively if you dont want to do that then add some colorful wallpaper behind the sofa. Where you have the table lamp add something taller like a modern floor lamp or a tall spread out palm plant. Take the table lamp and add to a side table if you have one. The second biggest issue is that you have a lovely modern sectional sofa and then you have paired it with a very traditional and very high coffee table that looks like it has marble inlay work done (cant make out clearly). This is not a good pairing. The coffee table is the right size but get something modern and a lot lower, a general guide to this would be one inch to 2 inches lower than the seating height of the sofa. As someone else mentioned an Ottoman that can serve as a coffee table in an alternate colour will also work. Paintings and wall art is something you can experiment with but unless you do something about the coffee table the room will continue to look odd in my opinion. Also some more shots of the room will help us get perspective.

Hello Shivani, For antique look, you can use an indian wooden swing as one seating on one of the sides of the seating, for wall treatment you can also go for pop textures with rust color on the wall. For the sofa go for a light color like beige or creme, with bright color cushions. You can also go for one seating in a contrast or bright color. Attaching reference pictures.