Note – This is my PERSONAL opinion, after going through the course.
CS50 : Introduction to Computer Science
CS50 is one of the best Introduction MOOC out there, and it is by the prestigious HARVARD University.
It is available for FREE, so I will definitely recommend my juniors to complete this course, over the first semester, especially if you are NOT from computer science background.
You can watch the lectures on YouTube – CS50 Lectures 2017
And you can access the assignment on edX – CS50: Introduction to Computer Science
This course is so praiseworthy, that I will revise it again in my free time.