Got a 15k EUR severance, parked it wrong for a year, trying not to repeat the mistake

Laid off early 2025, got around 15k EUR severance on top of my emergency fund. I'm 34, based in Tallinn, working again since last summer so this isn't survival money, it's just a lump I want to put somewhere sensible instead of letting it rot. Here's the embarrassing part. It sat in my checking account for almost a full year because I kept telling myself I'd "research properly" and never did. Rough guess that procrastination cost me 400 to 500 EUR in interest I could have earned risk-free. So th