How much time does one need to learn English or Russian in Tallinn, Estonia?
So, you have decided to set off on a journey called "Learning a Foreign Language", and you are face to face with the question of resources, including time. Congratulations :) This is a long and extremely exciting journey. Let's see how long it should take you.
On average, the first year will be spent on mastering the basics: pronouns, basic verb tenses, first words and constructions for everyday situations. Further, things will go faster, because you are already familiar with the language, you are already accustomed to the sound and logic of the language, and you can already - albeit with some help - work with authentic materials and apply the language in everyday life. This is what the next 2 years will be devoted to with the gradual complication of the materials, until you finally reach the level where you can participate in any conversation and extract meanings from the texts surrounding you. All in all, a year until first conscious usage, 3 years until more or less flexible practical usage.