When a spaceship travels in space, what life-sustaining substances should it carry and what can't be provided by space?

A lot. With the current technology of mankind, let alone maintaining life, it is impossible to get anything from the universe, including fuel. As for life support, there are water, oxygen and necessary food. At the same time, long-term flight needs sports equipment to prevent the loss of calcium in bones, and also needs various entertainment facilities to meet people's spiritual needs. Note that in the universe, the human spirit is easy to collapse. This is true for both physical and psychological reasons. Therefore, recreational facilities are necessary. Of course, this refers to a long flight.