Sir I am praveen.18 years... iam slim... and my frd sugested to go to gym... andi went.. 2 months... and I got chest.. and one side its some more and one side its some less... soo telll what happen s and how to corect it... and my weight is not yet devoleped.. I have eat lots of food a day.. but no change... so say how to increse my weight... waiiting 4r you are valuable replies sir

Break out the dumbbells and use a heavier weight on the side that needs to grow. If you are stronger on one side (and most people are) then it's easy to use the stronger side to lift most of the weight, but that makes that side even stronger. So you have to work the weaker side harder to make up the difference.

To put on more weight, you need to eat more. Simple as that. Try a protein shake directly after the gym, and perhaps before bed as well. I suspect you are not eating as much as you think.

Make sure the body you are aiming for is realistic. Some people just have a slim build and will always look best slim. You want to be the best, fittest slim you can be, not massive.