Gotcha, yeah, I'm not sure how they're connected exactly, but I have a sense of some of the differences.

You can be in ketosis indefinitely, by keeping your carb intake low enough. Your body will then primarily be burning fat for energy. My sense is that ketosis is primarily about switching from carb burning mode to fat burning mode.

Autophagy is a more desperate state for your body. It doesn't just look for fat to burn, but anything it can find. That includes a lot of debris that builds up in our bodies, like dead cells and virus fragments. As long as you have that extra stuff to burn, autophagy can be maintained, but eventually your body will start consuming muscles and organs.