Marriage Abroad Related

Hi All , I am Indian Citizen married in Vietnam. Our Marriage is legally registered both in India and Vietnam in 2021. My wife is having a son (13 years old now) from previous marriage. My wife is divorced and have court decree and custody of the child is in her name granted by Vietnamese court. But husband is having visitation right. I am staying in Vietnam from last 3 years and now planning to come back to India. I have following questions 1. Since my son birth certificate have his biological father name who is also Vietnamese. if I come back to India how will I handle the his school admission ? Even if he can get admission in Indian school will he be consider as foreigner national and all his fees will be consider in dollars or in Indian rupees ? 2. What will happen in long run regarding the inheritance of my property in India? What need to be done to make his life easy to handle all government related document ? P.S most probably I will be shifting to Gurgaon , Noida or Banglore