I am doing a school project about Bitcoin and more specifically point addition on the Elliptic Curve. I am very new to all this so please forgive my mistakes.

I have been reading that when adding points together the result can go "outside of the bounds before intersecting a third point" as in this image.

https://i.stack.imgur.com/6bh88.png

This is fascinating but also a little confusing and I would like to know more.

So my questions are:

1. Is it possible to know when the point addition process has gone outside of the field?

And

2. Is there a way (like a Python script or something) that I could use to add 2 points and it would tell me if the result went outside of the field?

I know that the result of the addition is still a valid point on the curve, but I would love to know if it passed out of bounds first.

This would be fantastic for my project to show others how this works.

I hope that made sense and thanks in advance for your help.