Here is the full list of all 23 Turnip Boy Robs a Bank achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Break into the Botanical Bank
Purchase an item off the dark web
Use the weapon rack
Research a weapon
Purchase a Robo-Roid
Steal $1,000 total
Steal $10,000 total
Steal $100,000 total
Steal $1,000,000 total
Defeat Yeehaw
Defeat the Rotten Candy Apple
Defeat Mecha-Chad
Defeat Uncle Rigsby
Find the Mysterious Motherlode
Find dad's stuff
Steal the Botanical Bank
Defeat the final boss
Take all the photos
Obtained all the hats
Puchased all the Robo-Roids
Purchased all the items from the dark web
Reached the max level in weapon research
Complete all tasks