Yes, Jorge.  Most of us here realize that you are a troll, and that is why you frequently ask such stupid questions and make such unimportant comments.

There is NOTHING inconvenient about the answer to your question, except that you should be able to figure it out yourself if you were more involved in buying and selling bitcoins.  Instead, you claim to have NOT purchased any through any service.

There are a variety of ways to acquire bitcoins by wiring money or by handing cash to someone or by mining or by earning them through a service or sales of a product.  Once you have the bitcoin(s), then you can use them to acquire Dell products or services (Dell chooses whether or NOT it wants to convert back to fiat and/or when to convert back to fiat, if it is going to convert).