In order to assimilate and differentiate these two words, it is necessary to define each of them.

Serve.

It refers to being apt or useful for a specific purpose. Like for example, you're good at math, it's good for business. "Serve" also refers to a succession of actions with different meanings, all of them associated with the same thing: the act of rendering service.

Servility.

It is an exaggerated inclination to serve or blindly satisfy an authority by going above and beyond your own values. As for example, I think that we are facing an unpleasant servility in front of the Venezuelan dictatorship.

Knowing the great difference, I invite you let's be helpful giving the best of us, helping others and collaborating whatever the problem or difficult, but without leaving our principles aside, all with the sole purpose of helping other people to achieve your goal.

As the phrase of Mother Teresa of Calcutta says:

"He who does not live to serve, does not serve to live."