Spoken language is acquired, not learned. This is a formal distinction in the literature, used (in general) to distinguish unconscious behaviors from conscious ones.
Learning involves something you have conscious knowledge about - you can learn how to build a birdhouse, and then you can teach me how to build one as well, because you’ve consciously learned the rules for doing so.
Acquisition is involuntary, and unconscious. Children don’t try to learn languages - any human infant given language input from any human language will acquire that language over time, seemingly without effort.
Also, the knowledge we gain from language acquisition is unconscious knowledge - as an English speaker, you can’t tell me why “John hit the ball” is a sentence of English and “John ball the hit” is not, other than to give an explanation that will eventually boil down to “because it just isn’t”. You don’t know why your language is the way it is - you just implicitly know exactly how it is, and how it isn’t.
So, acquisition being distinct from learning requires no magic - just an understanding of the differences between these two processes, in the same way as we can also understand the differences between writing and language, one of which is that language is an unconscious, acquired behavior, and that writing is a conscious, learned behavior.