Okay kiddo, so imagine you have a toy car and you want to play with it with your friend who lives far away. You can't just give them the car because they're not here, right?
But what you can do is take a picture of your car and send it to them on your phone or computer. That way, even though they're not physically with you, they can still see and enjoy your toy car.
In the same way, remote file sharing is when people want to share files (like pictures, music, or documents) with other people who are far away. Instead of physically giving the files, they use technology to make a copy of the file and send it over the internet to the other person's computer. This way, people can share files and work on projects together even if they're not in the same place.