Hi. I'm Adv Niharika.
Accorinding to Sec. 5(iii) of the Hindu Marriage Act, 1955, the age for a marriage to be legally wedded is 18 years for the bride and 21 years for the groom. The age difference between the bride and groom is based on the assumption that females attain maturity earlier as compared to males.
The Prohibition of Child Marriage Act 2006 and The Special Marriage Act 1954 also lays the above mentioned age for bride and groom, which is 18 and 21 years respectively.
Recently, in December 2021 a proposal had been placed before the Lok Sabha to raise the age of the bride from 18 years to 21 years.
I'm attaching a relevant article link for you convenient reading.
I hope this information helps. For further query you can contact me via email at Niharikalohan@yahoo.com