Communism and Totalitarianism are both types of dictatorships. Communism is seen as an ideology. There are no states, and there are no classes. With Totalitarianism, there is a state, and the state controls everything. With communism, society has all of the power. As the name suggests, Totalitarianism means total control.
Due to the state having all of the control, the individuals of the state have no place in helping with decisions. On the contrary, with communism, there is no control, and as a community, decisions are made. The community in communism also helps with gaining resources, while resources in Totalitarianism are gained from the state.