You may only copy, alter, distribute, or perform/display works that are entirely your own original work, which are in the public domain, or for which you have an exemption in the law or permission from the copyright holder.
Bear in mind that generally copyright protection is automatic as soon as an original work is completed.If you want the additional protection of formal copyright registration you will need to contact the copyright/intellectual property office in your country. For information on US copyright procedures see the related link below.
The web is not a place. The web is a communication protocol that is used for connecting computers together. The laws of the nation where the computer is located, or the user, or the copyright owners, determine what copyright laws apply, regardless of how the information is accessed.
There is a widely held, but incorrect belief that copyright does not apply when the work has been published on the internet, or that it does not apply if there is no copyright notice on something. There is also a popular myth that you cannot be sued for copyright infringement if you don't make any money on the unauthorized copies you distribute.
I think your question is asking about "public domain."
If copyright law did not apply to the internet, it would be nearly impossible to monetize anything on it.
Copyright law wouldn't apply to a skin care product, as it is not a creative work.
One must apply to the copyright holder for permisson to use their copyrighted item.
The copyright law of the country in which it was created would apply.
No; protection is automatic as soon as a work of sufficient originality is fixed in a tangible medium.
Most definitely
It varies from country to country. In the US, for example, it is US Code Title 17, the Copyright Act.
You probably wouldn't want to copyright a product; you might want to trademark it, or (if it's revolutionary) apply for a patent.