Can plants use nitrogen found in the atmosphere (n ²)?

No,

Although the atmosphere is mostly made up of nitrogen, it is in the form of gas known as dinitogen N2. Plant cannot use this form.

Explanation:

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.