The game can't proceed without an umpire.
An umpire needs to develop a good knowledge of rules of baseball; it is not expected you will know everything day one. A calm disposition and good communication serves the kids better than a "rule robot".
Courses are run at the start of the season with advanced courses held around the middle of the year.
An experienced umpire is always available to mentor and guide you along the way.
Watching some senior games is a great way to pick things up.