Sellers often provide tracking immediately after shipping, if not you can contact the seller directly.
Paypal is a great way to pay on eBay, it offers a lot of buyer protection. Although some sellers do accept debit and credit cards.
Due to many different sellers on eBay, best practice is to really look over the listing some sellers don't offer returns. If the item is damaged or faulty you can return it for a refund.
Simple way to bid, just place the highest price your willing to pay and you will beat the top bidder until you max price is reached.
Only in certain situations you can retract your bid if you made a mistake. If the listing is ending within 12 hours you can retract your most recent bid as long as its within 1 hour since you placed it.
Yes, eBay lets you shop even if you haven't registered for an account. They do have a few restrictions.
The only thing you can do is ask the seller to cancel it for you, just be nice about it. They can still leave you feedback.