The OED gives the first known UK published reference to 'paramedic' as occurring in The Economic Journal in 1966: "The I.U.D. cost estimate assumes a single insertion and one recheck by a paramedic".
Just like nursing (which, at one time involved little more than giving bed baths and emptying bed pans but is now far more complex), paramedic training has now advanced to full degree level. An outline of what is studied at university (which, of course, is supplemented by practical training) can be found by clicking on 'Course details' here:
https://www.plymouth.ac.uk/courses/undergraduate/bsc-paramedic-science