Avi Enterprises — Online work

Sir, i m a college student...
But i am a minor at the time of agreement
Avu enterprises called me and asked for job
I said i m minor madam
They told send ur mothers adhaar
And send some sheet and told to write my mother's name..
The job is of captheca filling
They told to enter 10, 000 captheca in 10 days
I asked them after my 12th exams i will do the job
They said ok in whattsapp
After my exams i tried to call but they didnt recieve the call
Now they are sending some notice and all
Blackmailing me to pay 6900 otherwise a legal action would be taken..
Please help me in this regard

And the signature was not made by mother
They asked me only to write the name

Help me