How do you say am in Hindi?

There isn't a direct equivalent of "am" in Hindi like there is in English.

Here's how you would use it in a sentence:

English: I am happy.

Hindi: मैं खुश हूँ (Main khush hoon).

* मैं (main): I

* खुश (khush): happy

* हूँ (hoon): the verb "to be" in the present tense for the first-person singular (I)

So, you would use the appropriate form of the verb "to be" (hona) based on the tense and the subject of the sentence.