For what I know, Catholic priests are studying Christianity in the convent for 10 years and live there. Correct me if I’m wrong, I seem to see some teens or very young pastors or maybe preachers coming out of some Protestant churches. Do I get it right?
Well, I think it would be unlikely that any church would appoint a teenager to pastor a church. However, there are and have been children who have preached sermons and even carried on evangelistic ministries. A book you may be interested in is
Out of the Mouths of Babes: Girl Evangelists in the Flapper Era .
It depends on the Protestant tradition and the specific denominational rules about ordination. Some Protestant traditions (Episcopalians, Lutherans, Presbyterians, and some Baptists) have strong expectations and requirements that their ministry will be educated (by that I mean at least a Master’s of Divinity from an accredited seminary).
Other Protestant traditions are very different. Many Pentecostal, Baptist, and non-denominational churches reject the notion that you need an academic degree to be ordained. Rather, their philosophy on ministry is that one’s calling to pastor, evangelize or teach will become naturally evident. It is the role of ordaining bodies to then recognize the calling that is already on the individual’s life through licensure and/or ordination.
For example, the Assemblies of God’s constitution actually states “formal academic achievement (diploma or degree) shall not be a requirement for credentials.” Nevertheless, the AG does have a process candidates for ordination must go through, and this process includes passing a standardized examination on Bible knowledge, AG doctrines, and ministerial practices.
My elderly great uncle (who attends church but has never seemed to me to be the “pastor” type) was licensed to preached by the Nazarene Church as a child (though I’m pretty sure his ministerial status probably lapsed long ago). He attends the Nazarene Church, but to my knowledge he does not preach or perform any ministerial function. His day job is as a nurse.
My grandfather is an ordained minister by his independent Pentecostal church, even though he is illiterate. He listens to the Bible on tapes.