Hi, thank you for your question. You are able to seek spousal maintenance for your reasonable needs even if divorce has not been issued, and in the course of proceedings you can seek support until a final decision has been made. This can be done using Form A and a £255 court fee to your family court.
In relation to the children matter, as you were married, the father has parental responsibility and you will not be able to change the child's surname without the father's agreement. If he does not agree then you will need to apply to court for a specific issue order under form C100 and a £215 court fee to your local family court.
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