Marrying a Brazilian

Since you will marry in India, you need to review India's marriage requirements and advise her.
Once married, have marriage accepted at the BR Consulate. While there or before the BR Consulate near you will have the information you will need to obtain a "family reunion" visa for you. (The Consulate can issue the visa, but the Policia Federal has the final say when you arrive.)
Gather and have all that needs to be translated and apostle/legalized and do so.
Now translation needs to be approved by the BR Consulate and again they can help.
You then can enter Brasil on a tourist visa and finalized the family reunion.

06/14/21

Anurag,

Congratulations!

The documents that your fiancée will  need to contract a marriage in India are determined by the Indian authorities, not the Brazilian authorities.  You'll need to ask your local authority that regulates marriage what documents a foreigner needs to present, and make sure that she brings them.

When the marriage is performed, do your utmost to have English versions of the Marriage Certificate and any other relevant official documents.  It will be much easier to obtain official translations of English-language documents in Brazil.

You and she should register your marriage as soon as possible after your wedding at the Brazilian Consulate responsible for your state.  Check that Consulate's website for "Registration of Marriage" to see the list of documents that both you and she will need to present at the Consulate for your marriage to have legal effect in Brazil.  Let her know so that she can bring those documents as well.  Sometimes requirements can differ a bit between Consulates, so be sure that you're checking the Consulate that has jurisdiction over your state.

If you and she decide to move to Brazil at some point, this Consular Registration will be a big help for you.