This is the 544th most frequent Italian word.
stare
"Stare" means "to stay," "to be," or "to remain" in English.
Here, 'sto' is used as an auxiliary verb in the present progressive tense, equivalent to 'I am' in English, indicating an ongoing action.
Sto studiando per l'esame.
I am studying for the exam.
In this context, 'stai' is used to ask about someone's state of being or health, equivalent to 'how are you' in English.
Come stai oggi?
How are you today?
Here, 'sto' is used to express one's emotional or physical condition, similar to 'I am' in English when referring to well-being.