Ah don’t be afraid of it. You’re missing out an opportunity to live a worryless retirement and to even leave a solid chunk of assets to your kids/partner. Simply invest a few hundreds euros (probably 300-400 will be enough) every month into an ETF which tracks some of the very broad market indices like MSCI World, FTSE All World or even S&P500. You have very good chances of becoming a millionaire or almost-millionaire by the time you retire. Good luck!