Antibiotics are strong medicines that treat bacterial infections. Antibiotics won't treat viral infections because they can't kill viruses. Some examples of viral infections are listed below -
Human immunodeficiency virus (HIV/AIDS)
Human papilloma virus (HPV)
Infectious mononucleosis
Mumps, measles and rubella
Shingles
There are treatments available for some viral diseases but no cure / antidote exist just yet. Antibiotics do not work against viral infections, they cant kill viruses. They are only effective in bacterial infections.
Hope this was helpful! :D