@QuantumX, No they do have free resources.

oxfordenglish site has FREE classes, here's the direct link: https://www.oxfordonlineenglish.com/...nglish-lessons

As for http://www.langcen.cam.ac.uk/lc/reso...e/english.html it does have resources that are not available at that site specifically but they are over the internet. For example:http://www.iausdj.ac.ir/ostad/DocLib...%20Writing.pdf mentioned in Writing Skills section of http://www.langcen.cam.ac.uk/lc/reso...e/english.html
You got to put your own efforts to get to these resources. Still if there's a book that is not accessible to you over the internet, you can contact any of facebook groups that send Free Literature. Or you may go to nearby library or ask your university to send you the ematerial.