It’s really hit or miss with finding copies of articles online for free without a paywall.
Often contemporary philosophers will post penultimate versions of their papers on their personal websites - so you can google them and look through their websites/academia.edu pages to try to find PDFs.
With more famous pieces they’ve usually been photocopied enough times to find them using Google.
With entire books or less famous articles you can try using “Anna’s archive” or “Sci-hub,” however these sites often violate copyright.
You can also try the Internet Archive to “borrow” books for free (you get access to a book for like an hour, and then have to sign in again…) If you’re having a lot of trouble finding something you can also use the ILL— Interlibrary Loan service). You’d have to ask Hunter Librarians for more information about this.
There are also Facebook groups that help people find things. I’m part of one called “Ask for PDFs from People with Institutional Access.” The graphic I’m attaching comes from their FB page. However, they do get mad at you if you ask for things that are easy to find using the graphic. Note that libgen and z-library have been taken down by the government.
Related note: How to read a scientific or academic paper