Dear Dharmendra Kumar as correctly noted by Arvind Singh and Carsten Weerth there is no COVID-20. It's just a myth / fake despite all the new mutations / variants of the coronavirus. Please see, however, this interesting link entitled
"Covid 20 - a blog post by Francesco De Meo"
In this article the author points out that "COVID-20 is what I like to call the disease that affects our society as a result of our handling of COVID-19." However, this is just a personal view.