The emergency telephone number (police, fire brigade, ambulance) is: 999
In fact, the 112 used by many European countries also works, it connects to exactly the same centre as 999. Both of the above numbers also work with a locked mobile phone.
The number 101 provides a connection to the police and is intended for cases where a quick response is not required, for example to report a theft that happened some time ago.
The number 111 can be used to contact medics if urgent and unavoidable help is not needed, but there are health problems.
Although the UK is no longer a part of the European Union, according to the signed agreement, the European health insurance card still works here.
If you are the victim of a theft or robbery, the insurance company may request an official report. Call the free number: 192
If you have lost an item on public transport, contact:
https://tfl.gov.uk/help-and-contact/lost-property?cid=lostproperty.
Unless you have a course of treatment prescribed by a doctor, it is not a good idea to take medicine with you to London. After all, some tiny wound plasters could be in the corner of the suitcase just in case. There are enough pharmacies in London to get, for example, medicine for a headache. Simpler over-the-counter medications are also available at grocery stores. Pharmacies are called Chemist's Shop or Pharmacy. There is also one pharmacy that is open 24 hours a day: Zafash, 233-235 Old Brompton Road SW5 (Earl's Court Tube Station).