In a medium saucepan, combine chopped strawberries, raspberries, and blueberries with sugar over medium heat. Stir occasionally for about 10–15 minutes until the mixture thickens and bubbles gently. Remove from heat and allow to cool.

In a large mixing bowl, beat room temperature cream cheese until smooth and creamy, about 2 minutes. Gradually mix in the heavy whipping cream and powdered sugar, whipping until light and fluffy, approximately 4–5 minutes.

Prepare the white cake mix according to package instructions and bake in a 9x13-inch baking dish at 350°F for 25–30 minutes. Allow the cake to cool completely.

Once cooled, poke holes throughout the cake surface about 1 inch apart. Ensure they're deep enough to hold the berry sauce.

Carefully pour the cooled berry sauces over the poked cake, allowing it to soak in for 10–15 minutes.

Spread the cheesecake filling over the berry-soaked cake, smoothing it out evenly.

Whip additional heavy cream until soft peaks form and spread or pipe over the cheesecake layer. Garnish with fresh berries.

Cover with plastic wrap and refrigerate for at least 4 hours, or overnight for best flavor.