Question

i have no pen ( interrogative)

Answer 1

Explanation:

$Haven't \: \: I \: \: have \: \: pen$

Answer 2

Answer:

Do I have a pen?

Explanation:

Interrogative: Do I have a pen?

Here ‘have’ shows the possession, not the ‘perfect tense’. Your sentence is a present indefinite tense, so it will take do/does as helping verb.

The first person singular(he, she, it and singular nouns) take ‘does’ whereas other pronouns and nouns take ‘do’ as a helping verb. That is why you have to put ‘do’ in the beginning of your sentence.

Similarly, if the sentence were ‘She has a pen’ then its interrogative would be ‘Does she have a pen?’.