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