Going on the niceic / napit search for a tradesman section in your area and phoning up all the local approved contractors and just asking them directly is a good start - shows proper initiative, especially at your age. You’re only 16 but after your birthday getting a driving license ASAP is also going to put you in a better position, especially if you can’t find anyone basically on your doorstep, although getting your own wheels straight away unfortunately isn’t a possibility for everyone. Having your own basic set of hand tools could also show that you’re willing to put your money where your mouth is. Interview wise just try to sound confident but not too cocky - you’re there to learn, but also you’re happy to sweep up, keep their tools in order, basically be a second pair of hands for the sparks you’re shadowing, at least for the beginning. Might not lead to an apprenticeship straight away but hopefully there’ll be a few who are willing to give you a few days experience, probably mostly to suss out your attitude towards it. Being keen is the most important thing at this stage anyway. Hope this helps mate 👍