Should I leave my bitcoins on the exchange after I buy? Buy Bitcoin Worldwide does not promote, facilitate or engage in futures, options contracts or any other form of derivatives trading. Only a legal professional can offer legal advice and Buy Bitcoin Worldwide offers no such advice with respect to the contents of its website. Chapter 3 Frequently Asked Questions. You can buy other digital items with PayPal and sell those items for bitcoin. Bank transfers, on the other hand, typically have low fees, but they may take longer than other payment methods.