Like just about anything these days learning Spanish is a service that can be found on the internet. Nowadays it is possible to order just about anything you want on the internet, so much so that you could probably live a very long time without ever having to leave your house or interact with another human being. How you can learn a language this way though is lost on me.
I guess it is possible to memorize words and grammar rules. You can gain an understating of the structure of the language and learn how to write and read; however speaking is a different matter. Personally I think if you learn Spanish only on the internet you are missing some of the important nuances that exist in the language. Your pronunciation will probably be horrible as you will have no one to correct you. Your conversational skills will definitely be lacking as you will have no basic knowledge of how to hold a conversation in Spanish.
In theory I assume it is possible to “learn” the words and form of the language on the internet but you will have no grasp of intonation or the many colloquial phrases used in everyday conversation; these of course being mostly specific to the country in which you are speaking.
There are many sites to learn Spanish on the internet, offering varying levels of assistance. Most require the purchase of software for true help as one would expect. They are worth it if you have no other way, but will probably leave you at a severe deficit when it comes to actually speaking.
I think the language is valuable, and I recommend to all that are able, to relocate to a Spanish speaking country where you can learn not only the language but also about the culture from which it stems.