When you talk about communism, are you talking about marxist-leninist / socialist states, or communism the idea(l) itself? Also how familiar are you with anarchism?

It seems that in the same way, people in this discussion have defined that communism is the mechanism for being generous and being willing to contribute to society.

You're not far off, but yes that is more or less all that "communism" is:

a classless, stateless, humane society based on common ownership, follows the maxim "From each according to his ability, to each according to his needs."

There is no prescription for how this may be achieved or how it might operate. Marxist-leninists want to reach it with a vanguard party and a socialist state, and this reflects how they see revolution as an event. Anarcho-communists instead see revolution as a process, and praxis takes the form of grassroots movements, aiming to bring about the necessary social change, building systems of free association from the ground up.