Yes, even if all of the biases are set to zero, the neural network model has a chance of learning.
No, training a model by setting all of the weights to 0 is impossible since the neural network will never learn to complete a task. When all weights are set to zero, the derivatives for each w remain constant, resulting in neurons learning the same features in each iteration. Any constant initialization of weights, not simply zero, is likely to generate a poor result.
