Yes, until the court rules otherwise.
absolutely
no
If he's paying child support yes.
No. Only the parents support the child, not the step parents. What you make will have no impact on how much he has to pay in child support. Even if you marry this woman that will not change.
no
No. This will require legal action.
No, there is no country on Earth that allows parent and child to marry.
At the moment in the US, Child Support is about $56 a week. YOUR income will not be effected, only his.
No, but send child support money.
No, only the NRP is responible for Child Maintenance.
No. Only the biological parents pay for their child regardless of who they marry.
If you're living together with the child, no; in such a case, get an order terminating support and setting the arrearage or stating that no arrearage is owed.