Your idea of breaking the wall directly to terrace is the first step. The opening need a wpc french window type opening with sliding or swing gate.

Dear Mr. Dinesh, Since you are looking for securiity with aesthetics, you need to incorporate a security grill in form of a geometric lattice/ jaali. You can choose between SS/MS or corten steel to do that. Second, you need light and ventilation along with weather proofing. Hence, it would be a really good option to go for anodized aluminium doors/ WPC doors which would be cost effective and decorative as well.

Hey Farooq, I understand your concern. I have a better idea. Drawing room and Living room does not need to be separated by a wall , you can just have a step up wooden flooring done in the drawing area to define the space. Also as per the plan what I have sent you, you can create a window where you existing Main door is and open up the Main door from drawing room as shown in red. If you still want want a wall between drawing room and living room then you can have it but it's just that I feel you can make your living room look big if you knock of the wall, or you can even create a partition with Jali work or you can even have a low height wall to just define the area. check out some of the images attached :)

Hi Farooq, you should go for wall paneling on that wall with a concealed door. The wardrobe can be a part of the unit in front.