There are several different jobs you can take on. Each has different recruitment requirements. (Note that this is not the same if you’re temporarily changing your job to enter a job-specific area. You can do that by using a disguise.)
Traveler – This is your starting “job” for a new player. A traveler can only stay in the kingdom for a year unless they become a Citizen.
Citizen – After going through the start of the tutorial and paying 5000 bea for a citizen application, you can become a citizen.
Student – A child character will become a student upon turning three years old.
Farmer – You can become a farmer just by accumulating work points throughout the year and then waiting until the end of the year. Having about 2000 WP is a safe bet to become a farmer.
Knight – Between the 1st and 4th of the year, sign up for the Cavalry Tournament (not possible during the White Night year). If you come in first or second in the tournament, you’ll become a Knight the next year.
Mountain Corps – Marry the oldest child in a Mountain Corps family to have the position handed down.
Scholar – Go to the Scholars Association Hall between the 29th and 1st and sign up (not possible during the White Night year). Then, between the 2nd and the 28th after signing up, earn adventure points to increase your rank. If you come in first, second, or third, you’ll become a scholar the next year.
Priest – You must be a second generation or later character, currently be a citizen or farmer, and have a high enough relationship with the priests for a priest (male) or curate (female) to name you as their successor, if you have already been an Acolyte by being single and having a strong relationship with an Acolyte.
Royal Family – A second generation or later character can marry the crown prince or crown princess to become royalty.