The maximum amount of points you can earn on a question is 2,000. You need to buzz in with the correct answer as soon as possible. If you're not concerned with winning the game, you can just buzz in any answer right away and hope it's right, or you'll just get it eventually through repeated playing. Once you start getting repeat questions, you'll start to get the maximum more frequently.
As with all BOS Achievements, this will unlock at the end of the round in which you get your 30th maximum point question correct.