Check out chapter 11 of this free book Rapid Virus Recovery.

Joseph Mercola recommends this treatment highly. This is from a preprint of his book The Truth About COVID-19

A heavily censored and ridiculed strategy that can be used either preventatively or acutely is nebulized hydrogen peroxide. This, I believe, is the safest and most effective COVID-19 remedy out there.

It’s extremely inexpensive, easy to use, profoundly effective — often eradicating symptoms within hours — and has no adverse effects or downsides when used at the very low doses recommended (0.1 percent, which is 30 times less concentrated than regular drugstore 3 percent peroxide).

Your immune cells actually produce hydrogen peroxide. This is in part how they kill cells that have been infected with a virus. It appears that nebulized hydrogen peroxide merely enhances your immune cells to perform their natural function more effectively.

You can also use it concomitant with vitamin C, as they likely have a powerful synergy and use different complimentary mechanisms.

Dr. David Brownstein published a peer-reviewed consecutive case series of 107 COVID-19 patients treated with nebulized peroxide and other remedies, including oral vitamins A, C and D, iodine, intravenous hydrogen peroxide and iodine as well as intravenous (IV) vitamin C, along with intramuscular ozone, in the July 2020 issue of Science, Public Health Policy, and the Law.

A critical part of Brownstein's treatment was one or two drops of Lugol’s Iodine added to the H2O2. See if you can finds the interview of him by Mercola.