New stutters or struggles in learning a new language

New stutters or struggles in learning a new language I'm currently trying to learn some Italian for a future trip. I switched from French cause it felt like a harder mental block with like half the letters not actually being said. So far Italian is better but I remember in school when trying to learn Spanish and I was never able to roll my R's. Any sounds or words you find impossible to work through when learning a new language? I stuttered all my life from what I can remember but got help earlier and long enough that it only comes out when really excited or theres just words I can't say still. I used to struggle with S, R, T, W, L as a child. That's my only thought to why I can't roll my Rs still.