The Immigration Rules do not allow a Short-term Student to bring family members to the UK.
Therefore, if you are applying as a Short-term Student and you have a spouse, partner, child or other person who wants to come with you to the UK, they must apply to come to the UK as standard Visitors.
A standard Visitor will be granted a maximum of six months' immigration permission, even if you have been granted immigration permission for more than six months. They will not be allowed to work but will be allowed to study if the study meets certain requirements.
If you are eligible, and choose, to apply under the Student route instead, your family might be able to apply as your dependants.