learning "quickly" depends on the person. It depends on the what kind of progress you want to make within a given amount of time. Maybe you'll reach an A2 level in 3 months, 6 months, or even a year. It all depends on how much you practice, why you want to learn it, how motivated you, etc. The time it takes to learn a language is different for each person and there is no universal way for everyone to learn a language quickly. Find what works best for you and stick to a plan that you make yourself.