It is true that getting your ears pierced with a gun is better for a variety of reasons, and it’s the best option for your ears.
If you don’t wear earrings once in a while, your ear holes will close and you’ll need to get them re-pierced. I’ve done mine thrice because of this. It’s more like a few months without earrings for them to close: but the newer it is, the faster it’ll close.
You wear the same earrings you did when you first got them pierced. Don’t change them for 6-8 weeks. Always wash your hands before touching them, dab your ears with rubbing alcohol, twist your earrings once in a while. When you get your ears pierced, you can ask further questions and you should be provided further info on care by a professional. You can wear headphones.
Where you want. Communicate with the piercer and they’ll tell you what is and what isn’t possible.
Some earrings are heavier than others, and some earrings do make your earlobes sag. Most will not. I have thinner and thicker pins on my earrings, but have never needed to enlarge my ear holes(?).
It depends. Cheaper ones can last with the right care. Price doesn’t indicate quality. Sterling silver is popular, and I prefer titanium for hardiness. Nickel-free is a popular choice for people with allergies. Different metals require different care.
No.