Take victory from pole position 41 times in your career
Qualify in first (pole position) and win. Do this 41 times and the achievement is yours. Changing the difficulty to easy will make it easier to qualify in first, obviously.
You can check how many times you've finished in pole position and how many wins you have (in your current season) by looking at your team-mate in the garage. You can also check your overall career statistics by looking at the "Standings" in your trailer and selecting your name. Unfortunately, unless you win every time you get pole position, there will be some disparity between the two numbers. Thus, you may be better off keeping track yourself.