File dynamics is like playing with blocks. You can build towers, houses, and all sorts of other things by stacking blocks on top of each other. In the same way, a computer file is made up of many little pieces of data that are organized and stacked together in precise ways.
Just like you can take blocks away or add new ones to change a tower, you can edit a computer file by changing some of its data or adding new pieces. But, every time you make a change, you have to be careful about how it affects the whole file. If you take away the wrong piece, the rest of the blocks might tumble down, just like if you remove the wrong data from a file, the whole thing might stop working.
Also, just like you might have different colored or shaped blocks, files can come in many different forms. Some are text documents, like a note you might write to your friend. Others are pictures, videos, or music. Each different type of file has its own rules for how the pieces of data are organized and stacked together.
Lastly, just like you can save your block creations for later or give them to someone else to play with, you can save computer files to use them later or share them with other people. Sometimes you might need to change the way a file is saved or the way it is used on different types of devices, but the core idea of organizing and stacking data remains the same!