Hi - you've probably come across these sources but Eurostat has information regarding ageing and population (which mentions persons in member states reaching retirement age): https://ec.europa.eu/eurostat/statistics-explained/index.php/Population_structure_and_ageing
Are you looking for the states' national retirement ages? The following has some general trend data (https://tradingeconomics.com/european-union/retirement-age-men).
Sorry if you already have this material and good luck with your research.