I was driving on the right lane and the cars in the front were turning left so I went to switch lanes. It was clear and the only car I could see was further behind. I went to turn and there was a car right next to me that continued driving with me on the side. And they completely blamed and I told the police officer I didn't see them. I have a dent on my door while they have small scratches. They said I have to replace the door, side mirror, and bumper. There are small scratches while I have a dent.

You were the one changing lanes, therefore it was up to you to make sure it was safe to do so. If you moved into another lane, and hit something that was already there, you are at fault. The fact that you "didn't see them" just shows that you failed to check properly that it was safe for you to pull over - because if you had checked your blind spot you would have seen them.

you are at fault because you failed to yield. it happens so don't worry. the trick is too turn your head all the way to make sure everything is fine because sometimes it seems like you can go but in reality there is a car coming or a cyclists and you can't see because the mirrors can't see everything. also you need to be able to judge vehicle speed distance before changing lanes. practice changing lanes if you have too to improve that

Definitely your fault you didn't look around thoroughly enough. He was in your blind spot

"I didn't see them" is only an excuse when you kill a motorcyclist with your car as determined by the courts and which you will, in all other cases you are at fault for not being aware of your surroundings. Do you own a smart phone by chance?

"I went to turn and there was a car right next to me"

Kinda say's it all!