Okay kiddo, let me try to explain. Substance use disorder is when someone has a really big problem with taking drugs or drinking alcohol. You know how we sometimes take medicine to feel better when we're sick? Well, some people take drugs or drink alcohol to feel better or to escape from their problems. When someone takes drugs or drinks alcohol too much, it can make them sick and hurt their body. It can also make them do things they wouldn't normally do, like hurt themselves or someone else.
When someone has substance use disorder, they can't stop themselves from taking drugs or drinking too much even if they want to. It's like they're stuck in a loop and can't get out. This can be really scary and dangerous for them and for the people around them.
The good news is that there are people who can help them. There are doctors and counselors who can help someone with substance use disorder learn how to stop taking drugs or drinking too much. They can also help them deal with the things that made them want to take drugs or drink in the first place. It's important to remember that substance use disorder is a real illness, just like being sick with a cold. And just like with a cold, it's okay to ask for help if you need it.