Translation:I have to go to Delhi to meet my friend.
I meet: मैं मिलता हूँ, I have to meet: मुझे मिलना है. For 'Have to do' forms of a verb, you use object pronouns (like मुझे) instead of subject pronouns (like मैं,) and the verb goes into its infinitive form, मिलना, instead of conjugating it at all. Then है finishes the sentence. I eat food: मैं खाना खाता हूँ. I have to eat food: मुझे खाना खाना है. (खाना means both food and 'to eat')