COVID-19 is an illness presumably caused by a virus named SARS-CoV-2. The illness is considered contagious, i.e., the virus spreads from person to person directly or indirectly. The virus is commonly viewed as a particle. For it to spread, the particle has to exist.
The problem is that such virus particles do not exist because no one has isolated them or positively identified them (details here).
If something does not exist, how it will transfer from one person to another. It can’t.
Therefore, wearing masks or keeping a distance becomes irrelevant. It is that simple!