You can find a birthday cake in every map in PUBG Mobile in many places. In Erangel it can be found in Yasnaya Curch and the red building outside the prison building. Can be found also in the Ban house outside Pochinki. In Vikendi it is available in the Port, the Villa, The Castle, and Dino Park. In the map of Sanhok, you can find it in boot camp, cave and docks. Miramar has the cake in El Pozo, Puerto, and Coberia.