How can I store water for many years to come without it going bad?

Store where nature keeps it frozen.

As in Modoc National Forest lava tubes that have existing year-around ice. 

If the bottle and the water are both sterile right up to the moment the bottle is sealed, it will remain sterile indefinitely.

Sealed in sterilized glass containers. The water doesn't "go bad" but bacteria can live in it for a long time 

simply put, water doesn't go bad, its the other stuff that's making it taste bad. This is just a theory that would probably work but is definitely expensive. if you are willing to try it you will need completely sterilized water and a completely sterilized giant glass container as it lasts a very long time (unless it's constantly being hit with blunt force) and it can be cleaned. Taking the water out would use extraction by distillation (heating up the water so that it makes steam hit the top of the container and collect at the end of a long pinched plastic tube) to prevent contamination. The glass container would have to be spherical or at least have rounded corners because using something to seal the glass together would make it more vulnerable to breaking or falling apart. I hope this was helpful...

Freeze it and keep in frozen. Be that as it may, if in 1000 years anyone has a 'need' for a thousand year old stash of 1000 gallons of water, then there would be far bigger problems that got egregiously neglected during that millennium.

i dont think you can

i dont think you can

I literally Googled "Long term drinking water storage" and it was on the first page of links.  Learn how to use the internet.

https://www.artofmanliness.com/articles/hydration-...