Okay kiddo, imagine you and your friends are playing with some blocks. You have different colors of blocks and you want to make a big tower together. But, you also have some rules to follow like, each friend can only use one hand to hold the blocks, you can only use one color at a time, and you can't knock over the tower. This is kind of like a group-scheme action.
In math, a group-scheme action is when a group of things (like friends) work together to change another thing (like the blocks). Just like in our game, there are some rules that the group has to follow to make things happen in a certain way.
For example, let's say we have a group of numbers (1, 2, 3, 4, and 5) and we want to change the order of the numbers. We can create a group-scheme action by saying that each friend can move one number to a new position, but we have to follow some rules like we can't leave any numbers out or repeat any numbers.
By following these rules, we can change the order of the numbers and create a new group. We could have moved the numbers in different ways to get different results, but we followed our group-scheme action and made sure everything worked together.
So, a group-scheme action is just a way for a group of things to work together and follow some rules to make something happen in a certain way. I hope that makes sense, kiddo!