The SoundFont Player can load .sf2 files. Many .sf2 files are available on the internet.
Use the SoundFont box to load one of the available .sf2 files.
The Import option allows for importing additional ones. Alternatively you can drop a .sf2 file on the SoundFont Player window.
The 'hamburger' button at the right hand side of the Import option provides access to the SoundFont Manager. It allows for adding categories and overriding soundfont names. It's similar to the Plugin Manager.
Use the Preset box to pick one of the presets provided by the current SoundFont.