It works.
It is necessary.
It is safe.
So say the results from two huge randomized clinical trials, one for the Pfizer/Biontech vaccine and one for the similar Moderna vaccine. Basically, if you don’t accept their results you should never ever waste your time going to see any doctor for anything because you do not believe in modern medical science, because there is basically nothing that the doctor can offer you for any condition that is as safe or as effective, other than some vaccines for other diseases.