Coronavirus has taken it serious form and also causes the death once damage the air passage ways into particular host. This virus is transmitted from the air droplets of the infected person. There are variety of responses agonist the Covid-19 by innate immunity that particularly recognized the cells of this virus as a pathogenic form and fights against them. It can be recognized through the pathogen associated molecular patterns. Type I IFNs are mainly involved in activation of other cells of immune system that contribute to immunity. Helper T cells are the main cells for defense against the viral cells. Helper T cells are the directors of the cellular immunity against SARS-CoV-2. There are different parts of the adaptive immune system work together, so seeing Covid-fighting antibodies, memory B cells, memory CD4+ T cells and memory CD8+ T cells in the blood more than eight months following infection is a good sign. Remdesivir as one of the antiviral drug binds to the particular cells of virus at cellular level by binding to the viral RNA. Tocilizumab as one of the approved drug by FDA for treating the Covid-19. Dexamethasone is used as potential drug to reduce the severe inflammation against the caused by corona virus. This drug has shown positive effects against the Covid-19.