Dentistry to Management Consulting

We definitely hire doctors in London.

I would make sure to research exactly what the job of a management consultant entails, what kind of projects they work on, what kind of tasks they do day-to-day, etc. For that, there are a treasure trove of articles online that all say virtually the same thing, so the source won't matter too much (here, Management Consulted, PrepLounge, CaseCoach, and so on and so forth + hundreds if not thousands of videos on YT).

Once you have a solid understanding, I would look at what the prep for consulting interviews look like (same resources although YT is nice cause you can see how it looks). That part is relatively important even if you're not planning on applying now, because the job will just be the same as a case interview but magnified a hundred fold. It will also teach you how consultants like to think.

Outside of that, I'd advise to build your business sense and acumen. This is fancy talk for business logic, which you develop by reading extensive business & finance articles. Basically build a foundation of understanding for key business & finance principles, what kind of problems corporations face, what keeps them up at night, what kind of decisions they make, what motivates them, etc. Read far and wide to get a lot of diverse exposure to different industries, problems, and business models.