Here is the full list of all 50 Titanfall 2 achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Destroy 3 enemy Titans with 1 Core ability in the Campaign
Destroy an enemy Titan as a Pilot in the Campaign
Kill a Caged Prowler in the Wildlife Research Labs
Acquire 6 or more friendly Stalkers at the same time in the Campaign
Perform a melee takedown while cloaked in the Campaign
Shoot and kill 3 enemies in a row while sliding as a Pilot in the Campaign
Rodeo an enemy Titan in the Campaign
Kill 25 infantry in 2 seconds as a Titan in the Campaign
Complete the Campaign on Regular
Complete the Campaign on Hard
Complete the Campaign on Master
Complete the rising world run
Defeat Slone
Find All Collectibles
Destroy a Titan with your Smart Core in the Campaign
Collect all of BT's loadouts in the Campaign
Call in a new BT
Shoot and kill 3 enemies in a row while wallrunning as a Pilot in the Campaign
Secure the Ark
Defeat Viper
Locate the Ark
Destroy a Titan with your Flight Core in the Campaign
Destroy a Titan with your Sword Core in the Campaign
Destroy a Titan with your Flame Core in the Campaign
Defeat Richter
Retrieve a working Uplink Module
Use the Arc Tool to activate a Stalker rack
Power the Beacon
Find the Arc Tool
Complete Special Operation 217
Destroy a Titan with your Laser Core in the Campaign
Find 25 Collectibles
View Anderson's first Holographic Log
Defeat Ash
Destroy a Mercenary Titan with a melee execution in the Campaign
Defeat the Reapers in Ash's Simulation Dome
Climb the Sideways Town
Enter the World Foundry
Find 10 Collectibles
Defeat Kane
Destroy a Titan with your Salvo Core in the Campaign
Keep Lt. Shaver and Lt. Freeborn Alive
Destroy a Titan with your Burst Core in the Campaign
Fully Powered BT-7274
Place in the top 3 on the Gauntlet scoreboard
Beat Pilot Anderson's Gauntlet ghost recorder time
Join a multiplayer network
Win a multiplayer match
Customize a multiplayer loadout
Complete training