Pugs are extremely, highly intelligent animals, and are one of the very few breeds of dogs that have a tendency to adopt or show "human" characteristics.
They are wilful, and have very individula strong personalities.
if you want to stay ahead of the game, and be in charge, rather than at their beck and call, you have to show equally strong characteristics.
This is a generalisation, and just like humans, pugs - and indeed, all breeds - have their strong, dominant, good-humoured, tetchy, wilful, obstinate, passive, calm and peaceful individuals!
Start as you mean to go on, and everyone will lead a balanced, normal, happy tranquil life, with everyone knowing, and happily adopting, their rightful place in the 'pack'!
Good luck!