If you separate one thing from another, you are detaching it. As a newborn baby, you became familiar with this concept as soon as your umbilical cord was cut!
You can use the word detach to talk about physically pulling two things apart. For example, when your shirt comes back from the dry cleaner missing a few buttons, it’s safe to assume they got detached during the cleaning process. This word is easy to remember when you consider its antonym attach. Once you have attached that election pin to your lapel, you better detach it when your candidate loses!