Enlarged adenoids. System of my kid?

Since January 2023 my son has started nasal problems like blocked nose and after consultation with the doctor we have given flomist spray 1time per day for 2 months using it he is feeling well again he has the same problem in June 2024 after continuing the medicine nasal spray flomist feeling well but now in December 2024 to till date in frequent interval cold ,cough, and sleeping apnea and snoring at night happens after consultation with paediatric doctor and using Nasomac nasal spray with electro homeopathy and histafree he is some control but still at night having sneezing with open mouth so today I consult the paediatrician doctor given me laveta M medicine with Nasal spray oxynix FT so my question is how to cure my child without surgery with elopathic medicines or if go for surgery then after removal of immune defense system any problem arises in future for my kid or not ? How to develop immune system of my kid?plz suggest sir or mam