You need to click the little camera icon in the outliner (the window in the upper right corner in the default Blender screen) for your Cube.001 fluid object.
This prevents the initial fluid object from being rendered. (since the fluid domain becomes the fluid when baked).
You can also click the eye icon to “hide” it in the 3DView.
Also, for your domain, the path should be “//cache_fluid” not “///cache_fluid”, You seem to have an extra “/” in there. -> the // refers to the current directory, so if you’ve saved your blend file at C:\data\fluidsim ,
then your baked fluid sim files will be saved at: C:\data\fluidsim\cache_fluid