Let's move to the questions of the activity. 1 -19 years for girls and 21 for boys feels like a good age to me for marriage because people are usually mature enough to take responsibility while still young enough to grow together. Parenthood can come a few years later.
2- A “right age” feels right when someone is emotionally mature, responsible, and ready to handle family life.
3- Emotional stability is a must, while financial stability is important . Although in my religion male have all the responsibility about finances but can grow along the way if both partners support each other.
4- Yes, I can imagine marriage or parenthood happening a little earlier or later, depending on life circumstances, education, traditional values and readiness.
5- I would tell younger people to first think about responsibility, maturity, financial planning, and whether they are truly ready for long-term commitment.