Okay kiddo, imagine you are walking on a street with your mommy. There are markings on the road which divide the street into several parts. These parts are called Lanes. It's a bit like a huge driveway where many cars can drive in their own space without colliding with each other.
Each car stays in one lane and cannot go outside of it. It's like when you're playing with your toy cars, you make sure each of them stays in its lane, right? Same thing happens on the street.
Sometimes, there is a special lane called a bike lane, where bicycles can ride safely without the cars bothering them. There can also be lanes for buses or taxis.
So, that's pretty much what a lane is, a way to organize and separate cars (and sometimes bikes and buses) as they move on the street.