There is no stated age anywhere in the bible or in any text books or laws, or in anything that has been written down, regarding ages. But maturity and God's will, should play the first part, and it is the most important issues should be taken into account before anyone goes further. But as not everyone is Christian, they go ahead without God's will, and then sorry to say, but they end up on marriage break ups, divorces and the children then get damaged by it.
If you are thinking of settling down, seek God in it. You probably heard this all before. But Who else can advise you better other than God himself? that's if you are Christian of course. Listen to God and learn of his will, give God your desires of your heart, Because he will know, what you really want. trust in his will. and trust in God in all.
Without God, you cannot mature into a true loving relationship and possible marriage and have beautiful children. As you know some marriages that will last more than a week. As you have probably heard, people getting married over night, and by the end of the week, they are seeking to divorce. Not saying that you are going to do. But those are people was without God as there centre piece of there lives. B
But Seek God. Pray about it. and listen to his will. if it is his will, then you will have a blessed marriage, because you seek God first, and involved God from start, and kept him in the centre of everything.
God Bless..........