> How can be made a web page, where you can pay for
> something with your credit card?
You pay someone to set it up. Simply put if you are asking you won't be able to do it. You would be much better off paying to get a site that would allow this. It's not simply click and it's done, and you don't want to be liable for any credit card fraud that may result from your site.
The first thing is to have an arrangement with some financial organization that will deal with the credit card companies on your behalf. (Obviously this is not a Java Programming issue.) Once you have that in place, they will provide you with instructions about how to interface with their systems. Follow those instructions.
> What should be the financial organization? Can it be
> a bank? If I meet with such an organization then how
> to make he web site to start selling?
This isn't the right place to ask about what financial organization to use. This is a programming forum. If you find one and need help working with their specific interface, then feel free to ask about that.