Thanks for your question. I will try to help.
If you do not have any UK ancestry and are not in a relationship with someone who has the right to enter and stay in the UK and intend to be employed as a paramedic then you would have to see if you are eligible for a Tier 2 General visa.
This is a form of sponsored worker visa, which his sponsored by your employer. The eligibility criteria is here:
You will have to see if there is a job that you could do in the UK on the shortage occupation list:-
See “Table 1 - United Kingdom Shortage Occupation List“ on the above link and you will see that paramedics are on this list.
So, if you were able to get a job offer form the NHS then they would apply to sponsor for the purpose of the visa.
If you find an employer willing to sponsor then you would then have to prepare your application and supporting documents evidencing your eligibility as per the above eligibility criteria link.
Once you are on your Tier 2 visa you will have to work in the UK for 5 years without leaving very often before you can apply for indefinite leave to remain. Once you have this you can apply to be naturalised as a UK citizen.
I do not know whether or not SA paramedics certification is transferable to the UK, so I would suggest that you investigate this yourself to find out whether there is any others courses that you might need to go on in order to “convert” your paramedic credentials so that they are sufficient to work as a paramedic in the UK. You should certainly check this.
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