Redistributive change is when some people who have more things or money than they need decide to share some of what they have with people who don't have enough.
Imagine you have a big bag full of toys and you're going to share some of them with your friends who have only a few toys. You take some of your toys out of the bag and give them to your friends. This is like redistributive change. It's sharing what you have with others who need it.
Sometimes it's not just toys that are being shared, but money or other things that people need to live a good life. When people with a lot of money or resources share with people who have less, it can help make the world a more fair and equal place for everyone.