| First you have not said what county you are from. This may make some issues. Also within the US, each state has its own rules somewhat.
But basicly you will have to petition the court where the child custody work has been done (normally since they were the orginal court of record on your custody agreement) If the biological father agrees ( will get him out of the child support) then your spouse can make petition to the court for adoption.
( it is all done at about the same time)
But I did not hear the magic word spouse, I only heard the word partner, which in todays society can mean many things, so depending on the state if in the US a partner may or may not be allowed to adopt |