How do tadpoles breathe underwater?

We know that frogs are amphibians that can breathe through their lungs and skin. But when they were tadpoles they lived completely under water. So obviously the breathing of frogs and tadpoles is different. So what's the difference here?

Tadpoles have many small gills, which help draw oxygen in the water through a thin film on the body.

According to US scientists shared on CNN, tadpoles have many small gills , which help suck oxygen in the water through a thin film on the body. Sometimes they float off the water to get oxygen in the air. As they grew up, their tails faded away and, as said, adult frogs breathed in their lungs; however, the uptake of adult frogs is also controlled through throat movements like tadpoles.

Breathing frogs without opening your mouth. The contractile movements of the throat help bring air into the lungs through the frog's nose, before being pushed out due to the contraction of their bodies. Although frogs use the main lung to breathe on land, they can also use their lungs to float easily on the water. In addition, the outer skin of frogs also contains capillaries to support their breathing.