To have a easier time getting the achievements in this game: Pause the game, go to Game Settings, select 5 lives and activate Round Select, you will get the achievements with ease this way
As the name suggests, you need to clear the fifth maze of the game, can be a bit tricky depending on your skills on Pac-Man, just eat all the Pac-Dots while avoiding getting caught by the ghosts, once you eat all the Pac-Dots, a small intermission cutscene will play and you'll get the achievement.
Also, make sure to eat the Cherry, Strawberry, Orange and Apples after eating a few Pac-Dots in Round 1, 2, 3, 4 and 5 respectively for a few achievements.
I also recommend avoiding eating ghosts so you can have some extra time to eat the Pac-Dots, 'cause if you eat them, they will regenerate and become dangerous again, only do it if they surround you or are chasing you.