OP, please try not to dwell on the worst case scenarios imaginable nor be drawn in by the fear mongering that is rife on social media. Also ignore the absolutely vile, nasty pieces of shit that have tried to put you down on your thread.
We are in a crisis and people are scared, that is understandable. But look at the positives.
If you do become ill, the people that will care for you, the people that will make decisions about your care, who are they? They are doctors and health care professionals, they are the best of human beings, they are people who have dedicated their lives to caring for others. They will not abandon you just because of some (currently hypothetical) tick in a box.
Yes, if the NHS becomes overwhelmed then there may not be enough care for everyone that needs it. But so much is being done to avoid that happening. The government is drafting in every medical professional they can, including asking those who have retired to come back to work. Any company that can is being asked to manufacture essential medical equipment. The government has said they will buy as many ventilators that engineering companies can produce and many firms are rising to that challenge. Capacity in the private healthcare sector will also be requisitioned.
This is the biggest challenge we have faced in our lifetimes but it is at times of extreme challenge that we invariably surprise ourselves by just how resourceful we can be, how much we can achieve.
Stay positive. We will get through this by pulling together, by supporting each other, by looking out for our friends and neighbours and even strangers we will never meet. That's how it works.