It can take years to find out what you want to do, and any random event can throw you off what you thought you want to do. I’m 21 and realised a couple of months ago I’m most of the way through a degree (aerospace engineering) that I will probably NEVER use.

Being an electrician or plumber is not the half way point between labourer and engineer by any means. There is a vast difference between the two and they are quite distinct. You can make a lot of money working in a trade if you get a good reputation or work for a reputable firm. There’s no reason to despair, almost nobody knows what they want from life at 16 and its more than likely that your life goals will change several times. If you’ve got no other idea you might as well stay in education and put the effort in in the event that you should decide to do something that requires you to have A levels.