In below Image:
We are using Dropout layer after 2 convolutional layers.Dropout will drop some neurons .Will it Drop neurons from previous 2 Convolutional layers or next 2 convolutional layers.How is it happening internally ,I am not getting ?
CNN 08 - Building Fashion MNIST CNN in Keras
Dropout layer is added for regularization of model, and making our model more robust.
Dropout layer, switched off some of the neurons in the previous layer only by setting their output to zeros. So coming to your question, it will drop neurons only in one layer, which is directly previous to it.
Hope this helped. 
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