Any tips for learning?

Hey guys, want to pick up French because my niece is learning. I took two years in high school, and I’ve been on and off using duolingo since; I graduated from high school in 2021. It’s just hard to get it to stick. Just wanted to ask for some tips on learning. I’m going to try and find my old notes, maybe that would help me, but I’m also going to try and take at least 15 min a day to learn with duolingo. Is Rosetta Stone a good option? Costs money if I wanna do all of it, but is it worth it? I’ve heard mixed reviews tbh. Does anyone know a good way to verbally practice too? I’m murmuring the words under my breath whenever I study on duolingo, and I’m listening to French songs to get the hang of learning it along with practicing the lyrics whenever I’m bored 😂 tbh works decently well (so long as I get the words right). Anything is appreciated, thanks!