See you both can marry once you are above 21 as that is legal age to marry, of parents are forcing her to marry someone she can lodge a complaint for that but your marriage at this point is not possible further more incentive you turn 21 marry under special marriage act.

Present a petition for your marriage to the officer of marriage/marriage registrar of your district, under the Special marriages act. Special marriage act was enacted for inter-religious marriages

Both of you carry aadhar cards and get married under special marriage act

you can get married under provisions of special marriage act 

2) 30 days notice of intended marriage has to be given 

3) if there are no objections you can marry each other 

4) in alternative girl can convert into Hinduism get married before arya samaj 

According to the Prohibition of Child Marriage Act, legal age for a girl to marry is 18 and for a boy it is 21. So, in your case, untill attains the age of 21, court marriage will not be legally possible. So better wait for one year after completion of 21 years you can apply for court marriage.

Dear Sir,

The following information may kindly be read and it is helpful to you both.

The following are the essential conditions to be fulfilled for the registration of the marriage under Special Marriage Act.

1. Neither party has a spouse Living
2. Neither party is an idiot or lunatic
3. Bridegroom has completed the age of 21 year and the Bride has completed the age of 18 years
4. Both the Bridegroom and Bride are not within the prohibited relationship

PROCEDURE FOR REGISTRATION OF MARRIAGE

1. Persons belonging to different relations and faiths can have their marriage Solemnized under this Act.
2. Marriages performed under other forms can also be registered under this Act.
3. The persons intending to register their marriage have to give notice thereof in writing in Triplicate in forms specified under second schedule under Section 5 to the marriage officer of the District in which at least one of the parties to the marriage have reside for a period of not less than 30 days immediately preceding the date on which notice is given.
4. After the receipt of the notice the marriage officer shall enter a true copy in the marriage notice Book and shall cause the notice to be published in the notice board of his office and also see that the notice is published in the office of the marriage Registrrsa in whose District the parties are permanently residing.
5. Any person before the expiration of 30 days may make an objection that the marriage contravenes the essential conditions noted above.
6. After the expiry of 30 days of notice the Sub-Registrar shall register the marriage after the Bridegroom and Bride sign a declaration in form specified in the Third Schedule in the presence of three witness and they should utter in the language known i(a) take the (b) I take b) to be my lawful wife. The parties may choose any other form like exchanging the Garlands ….etc apart from the above

By this process the marriage is deemed to have been solemnized and the marriage officer shall enter the particulars in the marriage certificate book and it will be signed by the partiers to the marriage and Three Witnesses.

The procedure of Registration of Marriage performed in other forms All the above procedure is same except that the utterance of i(a) take the (b) I take b) to be my lawful wife.

The parties may choose any other form like exchanging the Garlands ….etc apart from the above.

After the above procedure is over the parties will be issued an extract of the marriage register

1) You can get marry under Special Marriage Act and for your marriage related do let me know.

Dear Cleint,

Being major, both have freedom of choice to select life partner. File writ of habeas corpus in High Court. Court will order rescue from her parents and permit you to marry her under police protection.

You can only get married to the girl once your  attain 18 years of age, which is  legal requirement for marriage of a boy 

There is no illegality in you both being adult, staying together in a live-in relationship. Even supreme court has approved this relationship in a latest judgment.

Since you have not attained marriageable age, i.e., 21 years, you can live with her in relationship which nobody can object.

If you apprehend any trouble from any quarter you may better seek protection from police in this regard 

You both ca get married when you turn 21 years old under the provisions of special marriage act.

Prohibition of Child Marriage Act states that a girl in India can’t marry before the age of 18, and a boy before 21.

Wait till you attain marriageable age , after attaining marriageable age which is 21 both of you can marry under special marriage act

If parents forcing then lodge complaint against them

But I personally suggest you to try convince them don't hurt your parents 

If she is ready to change the religion then you may in Temple.

It seems that you are not financially independent and that is the reason that you cannot go ahead with your plans.

In case you get marry your age is not a problem for you and even if there is a case in the High Court to take to girl back and see testifies in the court that she is already married and wants to go with husband the court will allow her to go with you

For any further advice you need to call me after getting the details from this site