Is there a more detailed example of how such neural systems work? Like, what are the inputs? how the architecture of the network looks like? I ask because sen

Is there a more detailed example of how such neural systems work? Like, what are the inputs? how the architecture of the network looks like? I ask because sentences could be of any length, so I'm not sure what's feed to the model. My only experience with NLP is setting a toy text classifier using naive-bayes.