Thank you this legislation is for English law. However I you are seeking child maintenance you would do an application to the Child Maintenance Service. If you know the other parent's finical details (estimated salary) you can use tier online calculator to do an estimate of what they would require to pay. This is based on their income. Alternatively, you can come to a private arrangement with the other parent. If you require to make and application via the CMS, they will not back date this, you can only claim from the date you intimated the claim. Much fewer case are dealt with via the court.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
https://www.lawsoc-ni.org/solicitors (N. Ireland)
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