There is a slight naming clash though, for some institutions such as Cambridge and Oxford, where Cambridge university (for example) is made up of a number of colleges https://map.cam.ac.uk/colleges/

This is not the same as an independent institution which is a college (for example Cambridge regional college https://www.camre.ac.uk/)

Not necessarily, vocational qualifications in the U.K. (the NVQ) are often available at sixth-form colleges, but they will also teach the non-vocational A-level qualifications too. I don’t think there’s any consistency to what mix of vocational vs non-vocational certificate you can expect at an institution based on use of the word college.