What is truth? Truth means fact as it is.
What kind of person is a true person? A true person is the one who sees facts as they are and can say them as they are.
But just because you decide to live a true life doesn't mean you can do so. It is like, just because you want to become 10 centimeters taller doesn't mean you can grow taller that much.
Why do you have to lie? It is because you can't see facts as they are. Because you do not know the truth, that is, fact as it is, what you say is bound to be a lie, not the truth.
What does it mean to become a better person? it is that you make yourself truer. What is the way to make a better society? It is that more people make themselves become truer. However, in the present world, there is no interest in truth(fact) or the correct teaching of truth(fact).