How long does it takes to learn astrology?

Hello Kanu,
Astrology is science. Its like treatment given by the doctor for identifying the problem or issue.
Any astrologer can read astrology, Vedic system and give predictions, but real-life issues are different from each other, which are not written even in books.
So my point of view is how much knowledge you have either from books plus how many charts you have gone through and try to get the exact mapping of life events. Through analysis of charts and triggering the exact solutions to the clients with proper explinations .
It may take maybe months or up to a year, but not as easy as six months or a few weeks. It's like an ocean. Don't judge by seeing the waves of it.
A great astrologer is a lifetime learner, the more you see from the number of charts, the more you get a grip on it.