Here is the full list of all 23 Farming Simulator 19 achievements. It takes around 80-100 hours to unlock all of the achievements on Windows.
Sow 100 hectares
Cultivate 100 hectares
Fertilize 100 hectares
Harvest 100 hectares
Breed 20 cows
Complete 100 missions
Breed 30 sheep
Breed 50 pigs
Complete 50 missions
Breed 100 chickens
Harvest 10 hectares
Sow 10 hectares
Fertilize 10 hectares
Cultivate 10 hectares
Cut down 25 trees
Own a bank account with 10 million ingame money
Reach 10 hours of playing time in a single savegame
Complete 1 mission
Fertilize 1 hectare
Cut down 1 tree
Cultivate 1 hectare
Sow 1 hectare
Harvest 1 hectare