Thank you for the question. It is not good I am afraid, overstaying is actually a criminal offence unless there is a legitimate reason. However this is considered after 90 days, 11 years is obviously and excessive amount of time. You will not be legally permitted to work in the UK and if caught doing so a court can impose a custodial sentence. Therefore I would take this situation very seriously. I would strongly advise looking at instructing a solicitor in order to look through you best options moving forward based on your personal circumstances. If you apply for a visa you face exclusion and be refused re-entry to the UK for at least one year. I would look at instructing a solicitor as soon as possible.
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;
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