How can I get an angle using 2 Vector3 points?

I have a character with 2 points defined in him. One in his chest and one between his feet.
His feet are locked in place and when he moves the top half of him moves.
When his chest gets a certain distance away so he is on a slope (Like that michael jackson dance) I want to trigger a ‘step’.
How can I check when he reaches that point, or how can I check the angle of his feet to his chest along the Y axis?
so if(angle > 40) step();
Thanks

8709297--1176636--upload_2023-1-6_17-5-20.jpeg

You’re looking for Vector3.Angle/SignedAngle: