How much child support do I pay for 2 kids if I make $1,600 after paying insurance coverage for 2 kids who are mine, mom and 2 more who are not mine?

There is not enough information to be accurate but if you want a rough idea, you take your net income after taxes and after the health insurance and then take 25% of that and then multiple by 1.6 to get the amount for two children. There is no support for the children that are not yours.