I heard that using online resources, some of the top universities like MIT (Micromasters) and Harvard are offering free online courses and specializations. I wonder if there are institutions that offer graduate and post-graduate degrees totally free of charge(or almost).
As someone who has delivered both free and paid-for online university courses over the past ten years, with a reasonable grasp of the market in the English-speaking world, I'm fairly sure the answer is no.
At the moment the free short courses have a very different business model to a full degree offering - they either (i) rely on huge volumes with (optional) payment for certification or (ii) are essentially marketing tools, working as "tasters" for the real deal. It's hard to see how to run a full degree (with the necessary staffing, accreditation etc) for free. You might wait a long time to find one!
Alternatively, travel to Europe where real on-ground courses are cheap in many countries even for non-Europeans. If you enrol this year in Finland, the Finnish government is happy to cover your fees, but act quick, as fees come in in 2017!