I have a walmart intex pool and it's leaking.. . How do I find the leak?

Always start with places where the liner is connected to drain or filter piping. Also look at the bottom / side joint. If you don't have a deep sand base, rocks and roots can perforate the liner. Very hard to find. Squirt some food color around any suspect areas-an insulin needle is good for this purpose. The food color will be sucked out and disappear where there is a leak.