Yes, they were free to leave. No one stopped them from leaving the free trade area and having the exact same status as any other random country in the world. Or did you mean that Uk wanted to leave EU but keep all the good benefits? Like canceling Netflix and bitching about not being able to watch the latest series.
sure. It did just take 3 simple elections over many years, with open antagonizing, fearmongering and interference by the EU until they accepted defeat.