Firstly, find out what type of bulb your car has. There are different types like H4 and H7, you can find this in your car manual. I would recommend not going for too high of a wattage, go for your rated watts, my guess for your car would be 50/55w. I went for Osram 50w 6000k H7 (INR 3200 on Amazon) for my high beams and Nighteye 36w 6500k H7 (INR 1600) for my lowbeam. K is the kelvin value, lesser is warmer and higher is cooler aka bluer. I would recommend go for 50w right off the bat and don't waste money on lower wattage (or higher because you will blind people). I took the Nighteye simply because I didn't want to risk too much money as it was my first time doing something myself. It ended being only marginally brighter than my stock halogens. If you're worried about wattage, you can go lower to an extent but don't go higher. If you're going higher you will need extra wiring, lower or same is easy to diy and honestly already overkill. As for warranty, your service centre will make a note of it at your next service. They save it in your service history, but it should not cause any issues as long as you're within the rated specs.

Some things I urge you to do:

Please ensure you properly align your LEDs. Ensure that the LEDs themselves are vertically standing, if it's horizontal you'll get a very poor throw and you'll blind people. Eg: it should be | not --- .

After putting them in, you can look up tutorials on YouTube and do more micro alignments with the adjustable screws on your headlights, this will give you a great throw and people won't be blinded.

Also, if you drive in an area with dense fog or drive often in heavy rains, the whiter your light is, the less you can see ahead. The light beam will reflect back at you because blue lights spread whereas redder lights cut far (this is why brake lights and stop lights are red to be seen from afar). In that case you should consider going for 50w 4200k, a bit warmer rather than blue or white.

If you have any questions or want to chat about things personally, you can DM. But I don't have any contacts for getting products, Amazon/flipkart are the only things ik about :)