Now we get to talk about one of the things that a lot of beginners don’t know.
It’s another skill that you will need to develop and if you already have, in my opinion you’re off to a good start.

There are a lot of tools out there that can do this for you at least in part. I would encourage you to learn this skill it’s an intricate part of the setup process and if you get good at it your accuracy can be as good as automated systems don’t get me wrong, I do use edge detection tools just not for this particular job, I only work in relative coordinate systems in g-code terms g91 in relative coordinates.
I set the origin in fusion 360 and mirror that location on my machine by indexing from the part and the bed.

The other option is absolute coordinates or g90. In this system you have to place the part on the bed relative to the origin settings you’ve made. In the cam setup, absolute coordinates add a degree of difficulty to two-sided milling and for this reason I avoid it when i flip apart using relative coordinates. I only have to get the part on one axis with the machine using either an edge or a center line. In absolute coordinates I would have to match two accesses to accomplish the same task.