How can I keep my SSD mostly for Windows while storing other files on my hard drive?

Move your personal library folders individually. In File Explorer, right-click folders such as Downloads, Documents, Pictures, and Videos, open Properties > Location, and choose Move. For applications and games, select the hard drive during installation or change the download/library location inside the application's settings.

There isn't a safe single switch that moves absolutely everything away from the system drive. Windows and many applications still need system files, temporary data, user-profile folders, and configuration files on the SSD. Avoid manually relocating Program Files, the entire user profile, or system folders unless you know exactly what you are doing, since that can cause update and software problems.

In Windows, open Settings > System > Storage > Advanced storage settings > Where new content is saved. You can choose the hard drive for new apps, documents, music, pictures, videos, and other files. This covers many common save locations, although some programs still use their own settings.

You can keep large personal files and most games on the hard drive while leaving Windows and frequently used programs on the SSD. The SSD will still fill with caches, updates, temporary files, and application data, so check Storage settings periodically and remove unnecessary files rather than trying to redirect every system path.