Domicile is a fancy word for where you live and consider your permanent home. It's like your special place in the world, where you belong and feel most comfortable.
Sometimes, people live in more than one place, like when Mom and Dad work in different cities. But even if you spend time in many places, you can only have one domicile at a time. It's the place where you go back to when you're done with your adventures.
Domicile is important because it determines which laws and rules apply to you. For example, if you live in the United States, you have to follow American laws even if you are from another country.
If you move to a different place and want to change your domicile, you have to show that you intend to stay in that new place for a long time. This can be tricky sometimes, especially if you are constantly on the move.
In summary, your domicile is your permanent home, and it's important because it affects which laws and rules apply to you.