The verb "débrouiller" comes from "brouillard," meaning "fog." So it literally means "to de-fog." "Le Système D" is a famous piece of French slang in which the "D" may refer to "débrouiller"; there is a rougher alternative. See "https://en.wikipedia.org/wiki/System_D".
When telling French people you're learning French, 'tu te débrouilles déjà très bien' is a very common response if your French is already pretty good. For more uses of the verb 'se débrouiller' see my post in this forum: