Assalamu alaikum warahmatullahi wabarakatu, i'm 22yrs unmarried girl,i've thought to marry my childrens(in shaa ALLAH in future) at the age of 15 so to avoid any kind of a illicit thought

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

First of all, we ask Allah to facilitate marriage for you form a righteous husband and to bless you with pious offspring, and help you raise them up upon virtue, so that they will be a comfort to your eyes and your husband’s eyes.

Allah Says, when describing the slaves of the Most Merciful, (what means): {And those who say, “Our Lord, grant us from among our wives and offspring comfort to our eyes and make us an example for the righteous.”} [Quran 25:74]

It is good that you have this intention, may Allah reward you for it.

Since you are not married, then it is better to concentrate on the matter of your marriage, and to seek the help of your relatives or Muslim sisters in seeking a righteous husband for you. This is permissible in the Sharee'ah and it is permissible for you to propose yourself to a righteous man to marry you. However, in doing so, you should observe the Islamic conditions in dealing with a non-Mahram man. For more benefit in this regard, please refer to Fatwa 82471.

Protecting the children from temptations and its causes is Islamically required, and marriage is among those means and it is urged by Allah, if one is able to assume its responsibilities. However, marrying the children at the age of fifteen may have some negative effects in general, such as the inability of taking responsibility or being preoccupied by marriage at the expense of other matters that take a higher priority, a thing which may lead to problems in the future in marital life.

Allah knows best.