Chlorine injection, contact tank, backwashing coconut activated carbon tank to filter out ferric iron/rust particles and the chlorine.
Or, no chlorine. Backwashing iron filter, maybe cartridge filter, softener.
If limited to your list, chlorine injection, iron filter, softener. But you would need to be able to control the chlorine since you would not be taking out the chlorine. That would not be such a good method.
What is ppm of iron, and what other flaws does your water have? H2S? How deep is your well? Unless it is shallow, for bacteria you could probably just sanitize your well and plumbing once per year or so.