There are several professions that civilians can choose. Professions give you a bonus to skill gain and could give you access to producers or processors.
In most cases you need a specific skill level to get a profession. Changing professions costs 50.000$ and there is a 24 hour cooldown after changing.
Civilian professions
Miner
You can become a miner at the quarry if you have reached mining level 3. Active miners with mining level 7 also can use the mining quarry.
As miner you get a bonus on gaining mining experience.
Blacksmith
You can become a blacksmith at the forge if you have reached smelting level 3. Blacksmiths with smelting level 5 can use the local furnaces at the processing stations. When reached level 7 the furnaces at the forge is unlocked. Level 10 allows to repair wepons at the forge.
As blacksmith you get a bonus on gaining smelting experience.
Beekeeper
You can become a beekeeper at the beekeeping if you have reached honey spinning level 3. Beekeepers with honey spinning level 7 also can use the honey extractor at the beekeeping for processing honey that was be obtained from beehives.
As beekeeper you get a bonus on gaining honey spinning experience.
Carpenter
You can become a carpenter at the carpentry if you have reached carpentering level 3. Carpenters with carpentering level 5 can use the local table saws at the processing stations. When level 7 is reached the sawmill at the carpentry is unlocked.
As carpenter you get a bonus on gaining carpentering experience.
Refinery worker
You can become a refinery worker at the oil refinery if you have reached oil refining level 3. Refinery workers with oil refining level 5 also can use the machines at the oil refinery.
As refinery worker you get a bonus on gaining oil refining experience.
Tailor
You can become a tailor at the textile factory if you have reached tailoring level 3. Tailors with tailoring level 5 also can use the machines at the textile factory.
As tailor you get a bonus on gaining tailoring experience.
Parcel carrier
You can become a parcel carrier at every parcel station if you have reached parcel delivering level 3. Active parcel carriers with level 5 have a chance to get express parcels that have to be delivered in a specific time, but give you more money. Furthermore, active parcel carriers level 10 have the opportunity to receive an drop in the form of weapons or items with every parcel they deliver.
As parcel carrier you get a bonus on gaining delivering experience.
Crafter
You can become a crafter at the crafting station if you have reached crafting level 2.
As crafter you get a bonus on gaining crafting experience.