Academic research is contingent on building on past findings, much published in academic journals. While researchers get nothing from the journals when they submit their work (indeed, some pay for the privilege to get published), it can cost a fortune to access the articles. Only top, and wealthy research institutes and schools can afford this.
However, through various loop-holes, there are ways to access many, if not most, articles for free. One is to contact the author and ask for a copy, either direct, or through Research Gate, if they have a profile there. (My articles, are available this way, or a pre-print on this website). In my (limited) experience, most authors are happy to share, both because it is great that someone wants to read their work, but also because the vast majority of academics think the journal system is rotten and broken.
Other alternatives include:
To read about each of these, see this great article: