Getting your existing skills and knowledge recognised
APEL
If you have experience that has made you skilful and knowledgeable in some respects, it is possible that you could get some credit towards a course or a qualification. This is process is called accreditation of prior experiential learning (APEL).
APEL requires you to build a portfolio of evidence to so that competences can be assessed. It is always worth asking about APEL. Some professional bodies use it, for example, the Royal College of Nursing.
Many colleges and universities offer APEL, and the Open University has a long track record. There is information about APEL in adult, higher and further education on the UCAS website.
CATS
Many universities have adopted the Credit Accumulation and Transfer Scheme (CATS), and can take into account credits you have gained by previous study (if the learning is relevant to the university course you want to study and is not out of date).
ECTS
Do not worry if you got some or all your qualifications outside the United Kingdom (or wish to move away). The European Credit Transfer and Accumulation System (ECTS) is designed to make it easier to move around Europe, studying and working to gain experience. If you have international qualifications, you can check whether they will be recognised in the UK at UK NARIC. NARIC will charge you for this service, but much less than a course fee.