i’ve clicked all the options that are there but none of them put the z axis going up and down. i just want z to correspond to the global z axis.
It can’t put the Z up and down (ie, aligned with global world axes) because your Y is up and down, and your Z has to be orthogonal to your Y.
If you want, select the bone in edit mode, rotate 90 degrees in global X, then recalculate roll, and you’ll be able to have the Z axis pointing up. (90 degrees is assuming the bone shown is perfectly vertical.)