Hello. Without the information I asked for, I can only give you a general answer, but I hope this helps. You can always come back to me for clarification if needed.
The route to overturning the decision in the UK family court is via an appeal in the first instance. You can't apply to the European court until you have exhausted all possible options in the UK, which you have not yet done.
You normally have to appeal within 21 days of the court decision, so if more than this amount of time has passed you will need to explain why you did not apply sooner.
The form to apply is the N161 form, here:
You need to say in the application what your grounds of appeal are - this is the reasons that you think the judge made an error in law, in their understanding of the facts or if there was a procedural error that meant you did not have a fair trial.
You won't succeed if you are simply saying "I disagree with the judge" or "it is not fair" - so you need to have a think about the grounds and how you write these affects whether you will succeed or not.
I hope that this answers your question?
Thank you for your enquiry today. I am happy to answer follow-up questions - please do get in touch with requests for extra information or further queries and I will do my best to help you.