Here Is how to change the air conditioning filter on a Toyota Prius made from 2010 to 2015. This is how to change the cabin air filter on a third-generation Toyota Prius. Changing the cabin air filter on a Toyota Prius is quite easy. It is behind a little trap door in the glove box, and you don’t need any special tools to Remove the Toyota Prius A/C filter and replace it with a new one. The air conditioning filter on a Toyota Prius is in a little box with a tab on the right side that you depress to open a door and slide the filter out. Installing the cabin air filter on your Toyota Prius is the reverse of removal. Just put the new Air conditioning filter in, and then close the little door over it, and then reinstall the cover on the back of the glove box, and you’re done.

Here's where you can get a replacement cabin air filter for your Prius:
https://amzn.to/3xWm0Ac