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.
Cut down 1 tree
Cut down 25 trees
Sow 10 hectares
Sow 1 hectare
Cultivate 1 hectare
Harvest 1 hectare
Fertilize 1 hectare
Complete 1 mission
Reach 10 hours of playing time in a single savegame
Own a bank account with 10 million ingame money
Complete 50 missions
Complete 100 missions
Cultivate 10 hectares
Fertilize 10 hectares
Harvest 10 hectares
Cultivate 100 hectares
Sow 100 hectares
Fertilize 100 hectares
Harvest 100 hectares
Breed 20 cows
Breed 30 sheep
Breed 50 pigs
Breed 100 chickens