This is anecdotal and I am a sample of one, so do with this as you will. I have learned to speak French at two particular times. When I was very young, my Grandma Yvette often spoke French to me and I spent three years in French immersion. Now, I am an adult who barely speaks the language, but I have a daughter who I badly want to bless with the French language. So, I’m learning again... I have noticed two things. Th…
Pro tip from an immigrant who spent decade and a half trying to get good at English pronunciation - You need to practice in front of he mirror with a recorder and youtube nearby. Find a clip of french person saying a word or a sentence you're having trouble with and mimic them in front of the mirror. Again and again, try to see what muscle engaging on their face and do the same, think of what your tongue is doing. Remember you are building muscle memory and your tongue has literally never been in some of those shapes so you need to work it.
Pro tip two - find a pronunciation workshop or do a couple of sessions with a professional. Sounding like a native speaker is an incredible undertaking, but you'd probably be satisfied with being 75% there frankly.