You have raised two separate issues. The first is termination of the biological father's parental rights - if he has legally abandoned the child, you can ask the court to terminate his rights, which would leave you free to have the child adopted by your future spouse.
The second is the adoption issue. You must be married for a year before a stepparent adoption can be finalized. You do not have to be married the full year to start the adoption process, but you do have to be married before you can start. If the biological father consents to the adoption, then you do not have to go through the separate termination process, but if the bio father cannot be located or if he refuses to consent, then you would have to terminate his rights before the adoption could be finalized.
I recommend you speak with an attorney regarding your options and your best course of action.
** This response is provided as general information only and does not constitute legal advice or otherwise establish an attorney-client relationship. **
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