Do I need a patent or approval to sell my labeled product on Amazon, using a manufacturer's design with my label?

You cannot use someone else's design without entering into a licensing agreement. If you use someone else's design, someone else's patent, you aren't creating anything. You are illegally stealing their design and passing it off as yours. You need a licensing agreement.

The supplier would be in just as much legal trouble if they manufactured the unlicensed item for you.

However, you can simply buy someone's legally-manufactured packaging product and apply your own labels to it. You're selling a product inside the packaging, you're not selling the packaging itself.

If you own the rights to the label you don't need the patient or special permission for the water bottle. You might want to register the copyright on your label for additional protection.

I do not think you can "patient" water.

Nor can you patient a water bottle unless it s s dramatically different that you can claim unique.

You can Trademark the name of course and any logo you have come up with.

You can not copy someone else stuff its illegal.

You can't copy patented technology. So, if they have a patent, you can't make a similar product yourself unless you work something out with them (royalty or something). But if you buy the product from them you can sell it as you please.