No. Ireland and the UK are part of the Common Travel Area (CTA), a long-standing arrangement that predates both countries' membership of the EU and has continued since Brexit. Irish citizens do not need a visa, an Electronic Travel Authorisation (ETA), or any other permission to enter the UK, and can live, work and study there without needing to apply for status. You will still need valid photo ID for the airline and airport security — a passport is the simplest option, though it is not a legal requirement for Irish citizens crossing within the CTA the way it is for most other nationalities.