Question

find the error. India is very fortunate that it have many rivers

Answer 1

Answer:

India is ver fortunate that it has many rivers.

Answer 2

Answer:

India is very fortunate that  it has many rivers.

• HAVE is an auxiliary verb and in your sentence you have used the wrong form of the word.
• In your sentence you are talking about India that is singular.
• The singular form of have I has thus Has can serve as the correct form of the verb to be replaced with have in order to make the sentence have sense grammatically.