Thanks for your question.
As the partner of the child's parent you can apply for an adoption order if you are over 21 years of age, domiciled in the UK (ie. it is the place of your permanent home). The child must have lived with you for 6 months prior to making the application. You can make the application to the Family Proceedings Court and a Court issue fee will be payable (you can phone your local Court to find out how much.
You will have to apply using Form AS8 (Application for an Adoption Orde) with three copies and a certfied copy of the full birth cetificate for the child. There may be other documents you will have to submit, here is the link to the Form:-
You should also read the guidance notes first:-
If the abset father does not consent then you can ask for the Court to dispense with the requirement for consent if he cannot be found or the child's welfare requires that it be dispensed with (ie. it's in her best interests).
After issuing the local authority or adoption agency will prepare a report on the child and you/your partner will be asked for information. A first directions hearing will then be organised (about a month after you have issued) and your application considered. A final hearing will be timetabled at which the adoption order (is satisfied) will be made.
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