What helps them to breathe a banyan tree?

Banyan trees absorb carbon dioxide (CO₂) from the air through small pores on their leaves called stomata. A stoma (plural: stomata) is a pore found in the epidermis of leaves, stems, and other plant organs that regulates the rate of gas exchange. Each pore is flanked by a pair of specialized guard cells, which control the opening and closing of the stomatal aperture.

A single mature banyan tree can absorb a significant amount of CO₂ annually (measured in pounds per year) and release enough oxygen (O₂) back into the atmosphere to support the breathing needs of approximately two human beings.