You can't just change the one, even then. You would need the pair. Its also the wing (Fender) as the light is shaped differently so won't fit. So thats two lights, two wings, front panel, bonnet, bumper, bonnet lock, many other parts, wiring, perhaps wheel arches, the list goes on...
This will also need painting, fitting, etc. You will spend thousands on a car worth less then the sum of the parts!
Do you not have car breakers/dismantlers anywhere near you? It would be cheaper to drive a few hundred miles to source a used light, then do all the work, even if it can then still be done. Once you start you will be stuffed if you can't continue. It might even be easier to sell the car, advertised as needing a new light or buying a crashed one, with the light still there. Be careful not to also get the wrong type of light as you need projector and NOT reflector. If you get a reflsector, again, you will need to change a pair and they will need totally different wiring to operate. A whole new nightmare! Doable but again, not worth the cost!
The dealer should have not sold you the light so do your best to get a refund or you will be left with something that won't work.
In English terms, your car is worth at best, £2000 with the headlight and low mileage, etc. The paintwork, parts, fitting will come closer to £3000, if doable and then, the car will not be worth a penny more then when you started. A light will cost you around £100, less from a scrapyard/motor factor, eBay, etc and you can almost certainly fit it yourself or pay another £100 to get someone to do it.
I can only state again, you have the wrong part, you have the part for a newer, altered model of the same car. Put it this way, if the new light fitted straight from the box, I would have had a set on my car as the bulbs are supposedly a bit better. Carparts4less sell some, with a nice black tint to them. I would then have sold my own ones on eBay as they would be original Skoda parts.
FROM 2010, THE FABIA HAD A NEW, REDESIGNED FRONT END, INCLUDING ALL THE LISTED PARTS (BONNET, WINGS, GRILLE, HEADLIGHTS, BUMPER, PLUS OTHER BITS AND BOBS. They also had newer generation engines, new seat upholstery, plus various other bits. It was still a MK2 Fabia, called the facelift, as it was mostly the same but still SIGNIFICANTLY different. That is partly why after all the changes needed, the car will still not be worth more. It could actually end up being worth less, could cause great confusion when repairs are needed, and insurance (If needed in your country) May well go up due to the modifications. The only benefit would be a slightly unusual version of the car as it will be the old shape, with the later shape front end. There will be possibly one or two people who like the idea and perhaps offer a better price to buy, come the time to sell but most will start to think it was involved in a crash and repaired, using later version parts. Would you buy that?
In all honesty and again, I cannot say it firmly enough, try getting the money back for the part you payed for or sell it on again at perhaps a small loss as you have the wrong part. To attempt the work, unless you are in the trade or have someone you know in the trade, renovating and modifying will be a money pit, with no real benefit!
It might even be worth buying the cheapest Fabia you can find, taking the light and selling it again as a repairable... Perhaps stick your broken unit back in to look like it was ok, just needing the light. Cheap MK 2's are seen from around £800 in the UK. no idea again, how much they would be in India.
Oh, one more thing... The Fabia you refer to in the post, where the guy swapped the lights, wiring, etc IS A FACEFLIFT.
If you are thinking it is not, you are very wrong. I am now thinking you are considering the later, 2015 Fabia MK3, is the facelift. This was actually a whole new car. The facelift was around half way though the production of Fabia MK 2 (5J) As they started around 2007, facelift 2010, new model Fabia MK3, 2015.
Please take heed of this post as you will find so much trouble, unless you really, REALLY want to pay a fortune modifying your car. The whole point of this forum is to help others... I would not stress anywhere near this much, the point I have made, just to put you off.
Best wishes, Gary. (mrgf).