how to delete data without page refresh in thymeleaf spring boot using ajax

Question

I am trying to delete a record without refreshing the page using AJAX but I don't know where to start. The deletion works very well but the problem is that it refreshes the page. Can somone help me with the scripts that I have to add ? and also where should I add them,both for the springboot and thymeleaf pages

    public String delete(Long id, Model model, Principal principal) {
        adminPageController.getUserInf(model);
        if (principal == null) {
            return "redirect:/admin";
        }
        String gtype = "";
        Galerie galerie= new Galerie();
        Optional<Galerie> galerieOptional = galerieRepository.findById(id);
        if (galerieOptional.isPresent()){
            galerie = galerieOptional.get();
            gtype=galerie.getType().getName();
        }else {
            return "redirect:/admin/mediatheque";
        }
        if(galerie.getGalerieMedias().size()>0) {
            error="Galerie non vide, veuillez suprimer tous les elements de la galerie et réessayer";
            System.out.println(error);
            return "redirect:/admin/mediatheque/edit?id="+galerie.getId();
        }/*else {
            Set<GalerieMedias> gms=galerie.getGalerieMedias();
            for (GalerieMedias galerieMedias : gms) {
                galeriemediasRepository.delete(galerieMedias);
            }
        }*/
        galerieRepository.delete(galerie);
        return "redirect:/admin/mediatheque?type="+gtype;
    }
}```