How to get a stroke transparent

Looks like all strokes are expanded?

Then just select all and click on "Merge" in the Pathfinder panel (that button is in the bottom row !!!)

Afterwards ungroup and delete the pink things.

There will also be at least one invisible path.

Delete that as well.

Select you object.

Object > Expand Appearance

Object > Expand > Fill and Stroke

Object > Ungroup

Window > Pathfinder  > Subtract

Try with the Shape Builder (Shift +M) selected to drag over the pink areas while holding down the Alt (Option) key.

If the group of pink stroked objects is a separate group of objects with no fill you can apply a transparency effect to it using the Transparency palette.