This depends on which seat you're in, which model, and which year. Some models have no emergency release in the backseat for certain years.

Here's a model x, this feels pretty hidden to me: https://youtube.com/shorts/cfPhUY9erLM

This model 3 version has nothing: https://youtube.com/shorts/FWUWm9KaHzE

Here's the model y: https://youtube.com/shorts/FVwuOdMBpfo

I'm aware of at least three different versions of emergency release on the model 3 which vary greatly.