You can only gain any kind of immunity against any virus is via a vaccine. Close contact (herd immunity) with others doesn't make you immune and the human race are not guinea pigs, no matter what some "expert" claims. 14 months back no-one even knew about this virus.
Having said that, time will tell wether the vaccine actually works, all it will take is for few people who have had both shots, to catch covid19 and once again the world will be back to the drawing board. There are now a few new strains of Covid19 out there, are the current vaccines suitable ?
Also differ