How do I separate objects using the mirror modifier in Blender 2.82? I looked up the question already but they posts are from 6 years ago and the steps are outdated. The problem is that I added a mirror modifier to the shins and feet of my character. The question i how do I make the mirrored part an individual object. I have tried adding an empty axis but it didn't work the way I expected it to. When I select one, both are selected. Thanks]1

I put the bender file
https://blend-exchange.giantcowfilms.com/b/vzkE2NsZ
Go into the modifiers tab, and press Apply, on the Mirror Modifier. That will convert it to actual geometry.

Then, in Edit Mode, select one half of the object, and press P  > Selection. This will make it into a separate object.