I just wanted to ask is that possible to get a job after completing at least first 3 courses in a sequence.
Just the fCC certificates alone won’t get you a job.
Your competition is people with 4 year degrees - you need an equivalent level of programming skill to be a compelling hire.
Just completing courses is not enough. Have you built a few projects yourself? Have you learnt a framework or two? Have you used libraries? APIs? Have you used version control e.g. Git/Github?
Remember you are competing with other people, so the more you learn and build the better your chances of getting hired.