If i marry usa citizen girl who has children and then i divorce her then will i be need to give her

if i marry usa citizen girl who has children and then i divorce her then will i be need to give her child suppport too ?

If the children are biologically or legally (through adoption) yours, child support is an issue in your divorce case. Whether or not you have to pay child support depends on a number of factors, including the visitation timeshare and the disparity (difference) in income between the two parents. For a an in-depth explanation of the laws related to child support in California, take a look at this article:

https://cristinlowelaw.com/california-child-support-in-ten-steps/