How would you prepare and paint an exterior galvanized garbage can to avoid peeling, as it is exposed to freezing and harsh winters?

Which interior wood finish is best to use, to keep the wood trim looking white longer, oil based or water based?

I got instructions from minwax.com on how to stain and clear coat a fiberglass door. I have one coat of the clear coat on and sanded to put a second coat on. I did not realize you are not supposed to sand at all. The Minwax instructions told me for

I did some patch work on our bedroom walls prior to painting; then used Kilz interior acrylic (not oil based) to prime those spots. I didn’t read the fine print good enough….and I have now painted two coats of paint (with primer) on walls, and all the Kilz spots continue