You have too choices. You can do nothing and hope you do not get sick or you get vaccination and hope you don't get sick. I for one would do the later, following the advice of the most prestigious organizations of medical scientists such as the National Foundation for Infectious Diseases, the American Society for Virology, the American Medical Association, Johns Hopkins University, Mayo Clinic, Kaiser Foundation Research Institute, Harvard University, National Institutes of Health, ect...
According to best available scientific evidence, full vaccination followed by a booster is very effective at preventing serious illness from either the Delta or Omicron variants. And no it is not true that a new vaccine is needed for each new variant. To achieve maximum efficacy a new vaccine for each variant would be ideal but very impractical.
No vaccine can keep you from getting infected but the vaccines can give you a high a degree of protection against becoming seriously ill.