If you want to learn Spanish for free there are various ways of doing so; all of which have varying degrees of success
. By far the most effective way is through immersion into your local Hispanic or Latino neighborhood, ONLY attempting to speak Spanish. This may sound drastic or draconian even but it does have a good success rate.
But not all of us have the time or the inclination to put ourselves in this position to learn.
The other options to learn Spanish for free that are available to you are to borrow courses from your local library, this is a cheap and effective way to learn any language, never mind Spanish and well worth consideration.
The internet provides a host of free learning material to help you learn Spanish for free but what you will find can be quite fragmented; so it is always advisable to try and find excellent free material rather than snippets of poor quality, which unfortunately equates to the vast majority of what you will find.
In my opinion the one oasis of free learning material where the quality of resources in unquestionable is the BBC website. If you are looking to learn Spanish for free this is an excellent place to start, you will find a lot of resources at the bbc website. The one downside of this site is it lacks in interactive learning and to be fair it is this essential part of your studies that you will struggle to find for free, and that is unfortunate, as it is this area of your studies that will need the most attention.
You will find most aspects of Spanish available somewhere on the internet for free, but it is conversational Spanish that you need to concentrate your efforts on.
So yes, there are ways you can learn Spanish for free but you really need to invest in a good Spanish conversational course in order to achieve a good level of fluency.