Monster Energy Supercross - The Official Videogame 3

The achievement description is misleading, "The Real Thing" option is NOT under event type.
While going for this achievement I suggest going for "Not Today!", Reach at least 4th in last chance qualifier.

While at the Home Tab:
1) Go right to single player.
2) Single Event
3) 450
4)Race Options -> RACE Sessions, scroll right for "The Real Thing".
***Optional*** While in race options, set AI Difficulty to very easy.
5) Begin the series.

If you are just going for "What a Pro!", all you have to do now is qualify and win the next set of races.

If you are going for "Not Today!" as well;
1) Place any position in the qualifying.
*After placing a time, you can exit to the pit through the menu and hit session times and hold down the skip time button to make this faster.
2) Finish outside of the top 9 in the heat race.
3) Finish inside the top 4 of the last chance qualifier.

After you place top 4, the achievement should be yours. Then win the main event for the "What a Pro!" achievement.

-Happy Hunting