Yeah, that's easily the best way to learn how to speak and actually understand the spoken form of a language.
Think about it. Children are fluent in English by the time they're in the 3rd grade, and that's because they've been given consistent input from the time they could understand anything. A toddler will understand "get over here" even if they don't know what the fúck those words individually mean yet.
A language like Japanese would take you about a decade to fully master after consistent effort spent in a daily basis, but that's because it's so radically different from English.
If you prioritize the spoken form of it, you can probably become conversationally fluent in 3-5 years. There's a breh on base who works at the commissary who used this method to become fluent.
In short, he said that he put himself into situations where he'd be forced to speak Japanese. 3 years later, and his speech is as smooth as butter.