Most of the time minister is used in the Bible it is as a verb. It’s a action that people, usually priests, do to serve or worship God. Often these actions are commanded, or prescribed, by God in the Law of Moses.
Read in the Bible about this use of minister, which is primarily in the Old Testament.
Much less often the Bible uses minister as a noun in an appointed or approved capacity. It refers to a person who serves God.
Though sometimes, such as for Timothy, a minister oversees one church or area, usually the application is as a missionary who travels from town to town telling people the good news of Jesus. See pastor.
Read in the Bible about this use of minister, which is primarily in the New Testament.