Are you married to the mother of your child? Then you are automatically recognized as the legal father of your child.
If you are the biological father of your child but are not married to the mother, then you are not automatically recognized as the legal father of your child. You will need to formally acknowledge your child. If the mother gives permission, you can arrange this yourself at the civil registry without any complications.
However, it may be that the mother does not give you permission to acknowledge your child. You can then apply in court for substitute consent to recognize your child. Franssen Advocaten can discuss with you the possibilities with regard to substitute consent and assist in legal proceedings if necessary.