Procedure for Divorcce

Dear All I am writing on behalf of my colleague. She was Hindu before marriage but converted to ISLAM after getting married to a guy from Muslim community. After marriage they shifted to Bahrain, a boy was born after their marriage. Now after three years the husband has been cheating and committing adultery on her , the new girl in his life is from a hindu community and stays in india. Last time he left telling my collegue he is going to Dubai for some business trip, he went to India to meet that girl. shes knows this because she checked his passport and there were no Immigration stamps from Dubai. Apart from that she is afraid that he has already got married to her. Now she wants to apply for a divorce by going to India. She has not confronted him until now . Below Questions 1) What is best legal course that she can follow? Will muslim be applicable to her ? 2) What kind of maintenance she can claim for herself and her son? 3) Is polygamy allowed in Muslim law without first wifes consent? Please let us have your valuable feedback to help her out of this problem. She basically belongs go Mysore, India.