These are direct, official legacy installers from Trimble. Always scan downloaded files with antivirus software.
Downloading can be tricky because Trimble, the developer, officially retired it in 2017 and no longer hosts the installer on its main servers. It remains highly sought after as the last free desktop version of SketchUp that doesn't require a web browser or a subscription. Where to Find the Installer download sketchup make 2017
If you need a commercial license, you must buy SketchUp Pro (currently 2023/2024). These are direct, official legacy installers from Trimble