how to file for a contested divorce case

My sister got married 10 months back as per the Hindu Law. It was a arrange marriage and the groom's side has also taken money in the name of spending that money in marriage. After the marriage, they have realized there is lot of differences in opinion which is leading to daily arguements after which the boy asked her to leave his home one day. Both are well educated but my sister is not earning and facing difficulties beacuse of conservative nature and old school thought of boy and their family. They are not living together any more. We want to save this marriage but there ia lot of manipulation and lying from boys side which is making us loose hope in this relationship as this has become a cycle where they compromise but again same issue happens . We dont want this to be prolonged suffering for my sister. I want to understand all the legal formalities if in case circumstances leads us to court so that we can be legally strong as it is difficult to have evidence in these scenari