The internet is a unique place with both pros and cons to its usage. It is an absolute boon if you use this resource judiciously. Most students nowadays are tech savvy and are using online resources for almost everything from consuming web series to making and studying notes. In this generation when almost every thing is paid there are a lot of online websites that provide free courses for students of all ages.
NPTEL
NPTEL is stands for National Program on Technology Enhanced Learning which is an initiative by seven IITs, that are IIT Bombay, IIT Delhi, IIT Guwahati, IIT Kanpur, IIT Kharagpur, IIT Madras and IIT Roorkee and Indian Institute of Science (IISc) Bangalore for creating course contents in engineering and science.

Source; http://nptel.ac.in/faq.php
NPTEL has around 270+ courses from various fields such as aerospace engineering, agriculture, architecture, chemical engineering, computer science, humanities and social science, mining, textile engineering etc.
All the video lectures of the courses which are generally 40 hours long have been uploaded on their YouTube channels; https://www.youtube.com/user/nptelhrd/channels?view=60
NPTEL also provides for certification for these courses. For more details you can visit; http://www.nptel.ac.in
CEC UGC
The Consortium for Educational Communication popularly known as CEC is one of the Inter University Centre’s set up by the University Grants Commission of India. It Has been established with the goal of addressing the needs of Higher Education through the use of powerful medium of Television along with the appropriate use of emerging Information Communication Technology (ICT).
Source; https://www.youtube.com/channel/UCA7OQkX9AEIVQ6j9i0OSQhA
CEC UGC has courses ranging from literature, social science and management to music. You can find all these courses on YouTube; https://www.youtube.com/channel/UCA7OQkX9AEIVQ6j9i0OSQhA
SOL
The School of Open Learning was established under the University of Delhi in 1962 and is a pioneer institution in the field of distance education in India. 
Source; https://en.m.wikipedia.org/wiki/School_of_Open_Learning

School of open learning (Sol) provides for online study material for the courses which it offers such as B.Com, B.Com(Hons), B.A. History(Hons) ,B.A. English(Hons), B.A. Program.
You can find all the study material on; Sol.du.ac.in 
By Abhishek Kushwaha