I did French Immersion so that's like a solid 13 years of French study from age 5 on, I still couldn't call myself fully fluent but within a month of being in a majority French place i totally would be and learning it in school meant I learned the more technical aspects which combined with the grammar and shit for English means I can do alright enough reading Italian and Spanish as well. Not quite novel reading but I can do road signs and probably children's books level. If you get two languages based on the route under your belt you start to see the formula for all of them under that route.
I did French Immersion so that's like a solid 13 years of French study from age 5 on, I still couldn't call myself fully fluent but within a month of being in a majority French place i totally would be and learning it in school meant I learned the more technical aspects which combined with the grammar and shit for English means I can do alright enough reading Italian and Spanish as well. Not quite novel reading but I can do road signs and probably children's books level. If you get two languages based on the route under your belt you start to see the formula for all of them under that route.