The question of how to contact a person you were never introduced to, is not a question about mathematical research, so it is out of place here. (Perhaps you may contact some of your professors of fellow students with whom you studied, and who do research in mathematics, all depends on individual circumstances).
I will address the second part: how to get access to books and journals. Of course, this is absolutely necessary for study and research.
There is arXiv. www.arxiv.org. It is a free resource, and more and more people upload their results to this place. I believe that a majority of mathematicians already do this, and want to use this opportunity to call all the rest to join this majority. This is the only remedy against ongoing "privatization of mathematical knowledge" by big corporations.
You should try to get access to some good university library. This depends on a country of course. In principle, university libraries are supposed to be accessible to the public. You enter, you browse, and you can copy whatever you want, perhaps paying some charge for copying.
Unfortunately this free access is curtailed more and more with years, and especially bad situation is now, because of the epidemic. Paper subscriptions are eliminated, and for electronic access you need a university ID. Unfortunately, this is a worldwide trend now. The only thing I can advise in this connection: contact someone in your university (where you studied, or some other university) and ask whether you, as a former student, or as an independent researcher, can have an access to their electronic library resources. Some libraries may have computers on their premises which allow you access to their resources without an ID.
- There are many books and journals on Internet with free access. And finally there are "pirate sites". I do not recommend any particular one, because some of them may be illegal, in some countries. But finding them is not a big problem. They have very many books and journals for download.