Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking dish.
Prepare the red velvet cake batter according to the package instructions, using water, oil, and eggs.
Pour the batter into the prepared dish and bake for 30-35 minutes or until a toothpick inserted comes out clean.
Allow the cake to cool slightly, then use the end of a wooden spoon to poke holes all over the cake.
Pour the sweetened condensed milk evenly over the cake, allowing it to seep into the holes.
In a bowl, beat the cream cheese and powdered sugar until smooth, then fold in the whipped topping.
Spread the cream cheese mixture evenly over the cake.
Refrigerate for at least 2 hours before serving.
Garnish with red and green sprinkles before serving.