A health system is like a team of people who work together to help you be healthy and feel good. Just like when you play a game with your friends and you all have a different role to play, the health system has different people with different jobs to do.
The first person you might see when you're not feeling well is a doctor. The doctor helps you feel better by asking you questions about how you're feeling, and then may ask to take a closer look at your body to see if there are any problems. If the doctor sees a problem or thinks something might be wrong, they might send you to a specialist who knows more about that particular problem. Some specialists might be eye doctors, ear doctors or bone doctors.
But there are other people involved in the health system too. There are nurses who help take care of you when you're in the hospital, there are people who work in labs and test your blood to see if anything is wrong. There are people who make sure you get the medicine you need and others who make sure the hospital is clean so germs don't get you sicker.
In a way, the health system is like a big tree with many branches. The main trunk is the people who help us when we're not feeling well, but then there are many smaller branches that take care of different things like medicines and clean hospitals. The whole tree is there to help us stay healthy, so we can be happy and play with our friends.