A short-term study visa.
Please visit the Gov.UK website by clicking the link https://www.gov.uk/check-uk-visa or alternatively you can find lots of information on UKCISA pages: https://www.ukcisa.org.uk/Information–Advice

Tier 5 Youth Mobility visas
Coming from Japan, Korea, Hong Kong or Taiwan? You may be eligible to apply for a Tier 5 visa: https://www.gov.uk/tier-5-youth-mobility