Paranoia

Its on the very first level. You need to find a key in a desk which will open the locked door, thats the suirveillance room.

Brute Force

On the second level as soon as you found the shovel hit the lift with it.

Enlightement

I found 3 magazines and those unlocked the achievements, first was on the first level in the toilet room, second was on the third level in the office on the second floor (one level up with the small lift) on the shelves. The third was on the moveable object where you need move platforms to progress, you will know which is that area once you get there (look the magazine before opening the door with your keycard else you cant get it anymore)

Gluttony

After you felt down on a stairs you will find yourself at a native camp and you will see a crocodile which blocks the path to the canoe. In the village you will see a cauldron and meat in it. Get the meats with the raw you will find inside a small hut and feed the crocodile 3 times. for the fourth time get the fruit ingredients (for one you require a knife which you can find at the training dummies) and mix the right mixture from the fruits. You can find the required tool inside a small hut. The recipe for the rightr mixture in the big hut, check the eyes of the skull. Add the mixture to the cauldron then remove the meat, feed it to the crocodile and it will asleep. Use it only for the 4th time or after you got the achievement because you cant feed the croc anymore.

Flower Power

Try to unlock the lock with a flower in the graveyard

Earths suicide

Increase power to the max with the + button right at the end will make the earth explode

Healing Rain

Decrease power to the min with the - button right at the end and earth will be saved.

If you click on continue after you finished the game with one ending it will place you back to the decision spot right before the end but choising the different button will not reward you the ending achievement, sadly you need a brand new playthrough.

Summary

Requires 2 playthroughts, about 60-75mins to 100%