How can I complete the prerequisites for MS in Computer Science? 2019 application I have gone through: Similar question asked 4 years ago but this person had a lot of experience.

My Background: I am currently pursuing my bachelors in electrical engineering. I wish to pursue my Masters in Computer Science. I will graduate in 2019 (expected) with only 2 months of internship experience in Python (Data Science application). 

Country of Residence: India

Countries of Interest for University Applications: US, Canada and EU.

Probable MS start date: Fall 2019 / 2020

I have noticed that there are prerequisites to get admitted to those programs. Specifically, I need to have completed courses in Data Structures, Algorithms, Operating Systems, Theory of Computation, Compilers and Computer Networks. 

My undergraduate degree did have courses like C programming and OOPs, but nothing else. I took a computer course on Python at a local computer institute and interned during the vacation. 

With my current qualifications I am unlikely to get any meaningful work in CS so I would like to use a masters degree to start a career in CS.

So here are my options to fulfill the prerequisites:-

1) PG Course in computer science (Expensive; only distance learning mode will work)

2) Computer Science courses on edX, Coursera

3) Professional certifications like CompTIA a+ / Network+ etc. 

My major concern is whether Option 2 &amp;/or 3 will be considered by admissions committees? These may showcase my aptitude for CS, but will I still have to take UG level courses before pursuing a Masters degree?
Specifically, I need to have completed courses in Data Structures,
  Algorithms, Operating Systems, Theory of Computation, Compilers and
  Computer Networks.


These are the courses you'll need to complete then, and you'll need to complete them at an accredited school of some sort.  

Professional certifications like CompTIA a+ / Network+ etc. won't cover those topics at all, and simply wouldn't address these requirements. Some of those computer science topics are available on edX and Coursera, but most of them aren't accredited, or proctored, so the school you are applying to may not accept them. Edx does offer an online MS in Computer Science in collaboration the Georgia Institute of Technology, but you'd have apply for admission to that program, and they too will want evidence of having taken undergraduate courses in algorithms, operating systems etc. Also, when taken for official credit, the Edx courses are not cheap! 

That leaves you with option (1). I assume by PG you mean post-graduate. You should communicate with the school offering the MS, and see if they can offer suggestions for how this could be done. 

There is a remote chance that you could learn these topics by self-study and demonstrate your mastery of them to the school offering the M.S., but this is something you'd have to negotiate with the department you are applying to. The department would probably be highly resistant to this because many who claim to be self-taught really don't understand the depth of preparation required, and it ends up being a lot of work for the department for very disappointing results. Many people can teach themselves JavaScript, many fewer people can teach themselves the theory of algorithm design.