Very briefly and very simplified.
Having finished 9th grade, the pupils con continue in 10th grade, especially if they are still not sure what direction to go, or simply feel they are not ready for high school.
Some 60 % will go to high school for three years attending one of several main lines, like the classical mathematical or language line.
Many opt for what is basically 10th grade at a continuation school, where they live. Many if not most continuation schools have a specialty, like sports.
Some will become au pairs abroad.
Others will become apprentices, typically for 3-4 years as painter, hairdresser, technician, shop assistant and so on, with schooling in between working.
A few go straight from school to getting a job. That is actually discouraged though as it is the aim of the Parliament that all should have an education.
Some will later return to what is a kind of high school for adults, HF, lasting two years.
It is common for people who have graduated from high school or who has finished learning a trade to appear in front of the draft board, typically at 18-21 years old. In reality all who become conscripts are volunteers, some 98-99 %.
Men must appear before the draft board. Women can appear if they wish to and also sign up for volunteer conscription.
After high school many if not most will take a year off, before going to university, trade school or some other education.
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- So Christian: High school. Perhaps six months to a year doing something else, like working on a farm in Australia or travel. Draft board and volunteer conscription. Frederik and Joachim chose the army, but perhaps Christian will chose the navy or air force. NCO-school and officers academy.
Then in his early twenties Christian will attend university, both in DK and abroad. In between he will return to the military while moving up the ranks.