Choose a career and do an apprenticeship if you haven't already gone to university. No skills are required just your determination to succeed as shown in your application to the company holding the apprenticeship. You will be paid whilst studying on the job. This should be your first choice if it applies to you.
A full stack web developer. In university I taught myself how to build websites in literally less than one week. The syntax is dead easy to master on a basic level which is all you need to get yourself into the door. The hardest part is learning to code in javascript and or python. These two programming languages would take you at least 3-4 months to grasp the fundamental concepts. Light studying of school level algebra and physics (both based in logical thinking) will aid in the progress you make learning code.
Police officers make good money.
Firemen that drive the trucks make damn near £60k a year not even including London weighting which is another £3-£4K a year. All you really need to do is be under 200lbs and physically fit as well as be able to drive a car.
Train drivers in the UK after 12 months of training (probation period really) will start off making £56k a year not even including London weighting which is another £3-£4K a year. No skills are required, you just need to sell yourself well to get the job.
I'd go with web development because it is STEM and a career choice that isn't going anywhere anytime soon.