Please update your forum profile. It’s years out of date.
Why not just export the .stl file right out of SketchUp 2024?
You don’t with the native Save as … anymore. That was removed with the release of SketchUp 2024. There are a couple of Save as older version extensions available, though. A search of the forum here will turn up one by @dezmo and you can find one in the Extension Warehouse.