Obtain driving licence within 3 to 6 months

Did anyone learn driving in Japan and had obtained your licence within 3 to 6 months?
How to obtain a licence in a shortest span of time? How do I prepare for it?
How much will it cost?

Thanks :)

It takes practice. The more practice you get, the quicker you learn. Simple.

If you attend a driving school in Japan (like many locals would), that would cost about 300,000 yen in total. You'd get classroom lectures on rules, hands-on lessons on simulators, then you take the rule exam, take lessons on-premise, then you'd be out on public roads with an instructor next to you. As a college student I took the whole thing during a summer break, when I could take 3 lessons, for example, a day. If you are working in Japan and can take only 1 lesson or so in the evening, for example, that would take longer.