Help ! Help !

The first question I feel I have to ask after reading this post is - Do you WANT to teach or work in education? Forget about employment rate and chance of securing a job, is teaching something you actually WANT to do?
If it isn't, then you're better off doing your MA - teaching is hard if it's not something you want to do (it's hard if you do).
Can anyone please clear the employment picture after PGCE QTS to me ?
There are so many factors to take into account to answer this question. The demand for teachers in each area of the country varies, so it will depend on where you live, where you want to live, whether you can move for a job, etc. What is available now may be completely different to what's available in 2 years when you complete your PGCE - as you probably won't be able to start now until next September (unless you find a school direct or SKITT position that starts in January). At the moment, Social Science teachers are not "in demand", so recruitment to jobs available is probably stable - I don't know the recruitment figures for this year yet.
It's not possible to be clear.

Actually my main aim is teaching only , I have teaching experience of 3 years . I was having Mathematics as major and Political Science as minor in my graduation. I have teaching experience of 3 years in mathematics however due to my interest I wanted to shift to social sciences.

Fantastic, then go for the PGCE. Masters, PhDs are all well and good but they don’t necessarily make a difference for teaching secondary school - you may be able to negotiate a higher salary but you’d be able to do that with your previous experience anyway.
As a note of advice: job opportunities in maths are much higher as schools are desperate for maths teachers - so much that there is a bursary just for training. Once you have QTS you can teach anything as long as you can prove your subject knowledge 😉