Here is the full list of all 43 Mafia: Definitive Edition achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Found all copies of Gangsters Monthly
Found all 'Gangsters of the United States' cigarette cards
Found all of the hidden cars
Collected 30 vehicles in the Garage
Found a hidden car
Reached 50mph while driving the Bolt Ace
Lockpicked 5 cars on the streets of Lost Heaven and environs
Found a Mystery Fox
Resisted arrest by the Lost Heaven Police Department
Completed "The Death of Art"
Completed the game on Easy, Medium, or Hard difficulty
Completed the game on Classic difficulty
Completed "Moonlighting"
Completed "Just For Relaxation"
Completed "Election Campaign"
Completed "Crème de la Crème"
Completed "You Lucky ..."
Collected 15 vehicles in the Garage
Completed "Happy Birthday"
Completed "Bon Appétit"
Completed "Great Deal"
Completed "Visiting Rich People"
Completed "Omerta"
Paid a fine to the Lost Heaven Police Department
Completed "A Trip to the Country"
Completed "The Saint and the Sinner"
Completed "Better Get Used to It"
Found a copy of Gangsters Monthly
Completed "Sarah"
Completed "Fair Play"
Took Paulie to a Place of Disrepute
Won the race
Completed "Ordinary Routine"
Completed "Molotov Party"
Found a 'Gangsters of the United States' cigarette card
Found a Pulp Magazine
Completed "Running Man"
Completed "An Offer You Can't Refuse"
Lost the cops after accruing a five star police chase
Performed a wheelie for 3 seconds
Found all Pulp Magazines
Found all Mystery Foxes
Completed the Collection