You'll want to poke this poke cake with a fork. Probably repeatedly.
Grease the bottom of a square 9" baking tray and line the graham crackers on the bottom (break apart if you need to).
Pour in the prepared vanilla cake mix and bake for 25-30 minutes at 350 degrees Fahrenheit. Evenly poke 1/2" holes on top (4-5 lengthwise, and 4-5 widthwise).
In a bowl, mash the strawberries and combine with the cream cheese, and condensed milk. Whisk together until smooth and creamy. Pour in the milk and stir. Pour over the cake.
Evenly top with the whipped topping and chill for 3 hours.