If you have family members (a husband, wife, or children under the age of 18) and you want them to join you in the UK while you study, please check carefully that they are entitled to come to the UK as your dependants. Be aware that the rules may have changed since your last application. The UKCISA guidance on Bringing your family is a useful tool to check if you are able to bring family members with you to the UK.
Once you have checked that they are eligible, each family member will need to apply for an Entry Clearance visa to come to the UK. The UKVI website has guidance about supporting documents and the maintenance requirement for family members and information about how to apply from overseas.