A Tier 4 (General) Visa is required for studies in the UK if you are over the age of 16.
If you’re 16 or 17 and you want to study at an independent school in the UK, you may be eligible for a Child Student visa instead. If you fit in this age group, you should talk to an immigration advisor because this can make a difference on how long you can stay in the UK.
anyone under the age of 16 must apply for a child student visa.