i tried for 3 years of self study plus some weekly in person lessons. Heavily grinded anki , did pimsleur, michel thomas , duolingo.
Overall i would say it was a failure, got to where I could read almost anything , but completely failed at being able to have real-time conversations.
I think for me I would need immersion to really get to the next level. Like I would need a french person to live with me for a few months.