There are no medicines or remedies that have been shown to prevent or cure COVID-19.
Hot water with lemon and honey, vitamin supplements, foods with garlic and ginger, apple cider vinegar, gargling with saltwater, none of these things has any impact on human immune response and would not eliminate the coronavirus. These claims are considered as myths but not fact.
There are a variety of suggestions that suggest heat kills the virus, from recommending drinking hot water to taking hot baths or using hairdryers. But, there's no evidence that it will protect against coronavirus.
The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19 including symptoms, prevention and available treatment, please refer to the World Health Organisation or your national healthcare authority.