Praise be to Allah.
You have done well to refuse a wedding in the Hindu manner, because that is not permissible for a Muslim, because it involves committing falsehood and approving of it.
The Islamic wedding party does not have a particular format that must be followed. It is prescribed to bring happiness to the husband and wife at the wedding, but that is on condition that it be free of evil actions. See the answer to question no. 82500.
Evil actions include mixing of men and women and imitating the Hindus in their adornments and clothes that are unique to them.
We have heard – in questions submitted to this website – that which indicates that the Hindu style of weddings includes the wife sitting on a chair, fruits and food are brought to her, and men and women feed her. Then the “holood”, which is a kind of adornment, is placed on her head. If this is indeed the case, and these men are not your mahrams, this mixing is haraam and the fact that some Muslims do it does not make it permissible.
With regard to adornment, if it is something worn only by Hindus, it is not permissible to wear it, because it is haraam to imitate the disbelievers in that which is unique to them, as the Prophet (blessings and peace of Allah be upon him) said: “Whoever imitates a people is one of them.” Narrated by Abu Dawood, 4031; classed as saheeh by al-Albaani in Irwa’ al-Ghaleel, 5/109
If the marriage will be done in the Hindu manner, this means that you would be imitating them in their customs, clothing or adornment, which is haraam.
You should try hard to convince your parents and talk to them gently, so that you can have a celebration that is free of evils.
We ask Allah to increase you in knowledge and guidance, and to bless you.
And Allah knows best.