Secure Housing Executive (NIHE) and housing association tenants have a right to buy the home they live in, as long as they and the property are eligible for the scheme. Housing association tenants must apply by 28 August 2022.
You can add someone else to your tenancy. But, you need your landlord's permission to do this and your landlord can refuse in some circumstances. You don't have to add people who live with you to your tenancy.