Crossway Technology — threatening and blackmailing for money

I was looking for work from home option for part time job. searched the same on some sites without. On 28 Jun'19, i got the call from one lady and she told me about this job. She told its free and with prior intimation of week you can inform us if you dont want to work (the work was as per them pdf to word conversion of captchas). And got an agreement in pdf with digital signature.
I was continuously mailing to that company that I dont know how to work, who will tell me what to do, not received login-pwd etc.
Finally, i received login details. Again same problem, that i was not able to work as I dint know what and how to work. I tried their customer care number but all the time it ws busy. I mailed them, they called me back and said try b/w 1o am to 2 pm, you will get assistance.
Still no response on call (as it was busy).
Then as per my best uderstanding, i loign the site and found some captchas there, and one box was there, i typed it and it moved to next...so I typed some count of them. But, it was not the work which we agreed and working on that ste was too slow. Then I mailled them within next day, that I will not do this work this work and cancelling the term.

After that, threatening and blackmailing calls started to me and stil ongoing. I old them that I am getting mentally harassed but them dont bother and calling from N number of different numbers. Now they saying, sending legal notice in my home.

The mailed I am getting from :
helpline.[protected]@gmail.com
nishi.[protected]@gmail.com
sharma.r.[protected]@gmail.com (claiming that he is advocate)