There is LITERALLY not enough water on the planet to dilute a single molecule of compound to the dilutions homeopathy experts claim.
I thought that their drugs were diluted to about an order of magnitude less potency than normal, to something like the level for training the immune or allergic systems to tolerate hostile substances.
Dilutions vary, but the kind of dilution you're referring to isn't really what homeopathy is all about. That's just cheapskating on doses.
The idea behind homeopathy is that if you mix an active compound with water, then the water molecules will kind of form around it and take on the inverse shape of the molecule, like a molecular mould. The water molecules supposedly keep this shape, and with it, the activity associated with the medicine. The "medicine" is then diluted to the point where no active molecules are present, because medicinal compounds carry with them the risk of side-effects, which the dilution is supposed to eliminate.
I'm not joking. That's genuinely what they think happens when you dissolve something. Of course, the fact that the dilutions are so enormous that it's physically impossible for any amount of active compound to have ever been inside any of their factories is often conveniently overlooked.
Generally a filler compound, often camphor for liquids, is added, to give it some smell and taste so people don't immediately notice it's just water. For solids, they often use sand or other oxides.