The University Preparatory Programme is an adult education programme, so you need to apply for an “other type” visa if a visa is required to enter Hungary. This type of visa/residence permit does not allow you to work. Employment is not recommended due to the high number of lessons.
If you have Hungarian citizenship or live in a European Union member state, you do not need a visa to enter.
You will also find information about entering Hungary and visa on the following pages:
Visa-free travel to Hungary: https://konzinfo.mfa.gov.hu/en/visa-free-travel-hungary
How to Apply for a Visa: https://konzinfo.mfa.gov.hu/en/how-apply-visa
EU Visa Facilitation Agreements: https://konzinfo.mfa.gov.hu/en/eu-visa-facilitation-agreements
List of Third Countries Where a Schengen State Issues Visas on Behalf of Hungary: https://konzinfo.mfa.gov.hu/en/list-third-countries-where-schengen-state-issues-visas-behalf-hungary