The COVID-19 infection is caused by Betacoronavirus named SARS-CoV-2 (Severe-Acute Respiratory Syndrome Coronavirus-2), which was originated in China in 2019 and spread, all over the world. In the case of SARS-CoV-2, the binding of the angiotensin-converting enzyme 2 (ACE2) receptor and the spike proteins of the virus leads the viral internalization, which initiates the innate immune response. The infection starts with different types of interactions of virus with host cells, and these interactions can be modulated against the infection of SARS-CoV-2 by blocking the ability of ACE2 host receptor to avoid the spreading of disease. The glycosylation of spike protein can be modulated to alter the affinity of ACE2 receptor to affect the infectivity of virus. In this review, we have summarized the mechanisms of spike protein-host cell interactions during infection to develop the immune response and how the modulation of these interactions can help develop vaccines.