What do you call a person who doesn’t talk much?

A person who doesn't talk much is often referred to as a "quiet person" or a "reserved person". This is because they are typically not very vocal and may prefer to keep their thoughts and feelings to themselves. They may also be introverted, meaning they prefer to spend time alone and don't particularly enjoy being around large groups of people. They may also be shy or have difficulty expressing themselves in social situations.

It's important to remember that a person who is quiet or reserved doesn't necessarily have a mental health issue, and it's important to respect their boundaries and not force them to talk if they don't want to. It's also important to be aware that some people may be quiet due to underlying mental health issues, such as social anxiety, and it's important to be understanding and supportive of them.