For questions about the training of Jedi, accomplished by spending many years learning the ways of the Force to become a Jedi Knight. Always use in conjunction with the [star-wars] and [jedi] tags.
To become a Jedi Knight one must join the monastic spiritual order of the Jedi.
Young learners, called Younglings and then Padawans, are typically chosen while young children and they will spend many years studying, serving and learning the ways of the Force through passive meditation, practicing selflessness, and commitment to justice while at the same time rejecting emotions such as passion, fear, anger and hate.
See the Wikipedia page for more information.