As Mr Magoo says, the lack of A levels is absolutely no barrier to entering the maintenance engineering professions, and there are plenty of threads in here about how to do that - just use the search function.
If you want to do a degree, then A-levels are the most common route in, but there are various direct access courses available. A foundation year won't do it - those are for people who have the wrong A levels, not people without. Also, to be honest, the FoE (Foundations of Engineering) year in most universities is hard going with poor learning support and enormous class sizes - you'd be much better going to the local sixth form college or equivalent and going straight into level 1 with A levels.
Incidentally, I can't for the life of me see how you can be good at maths but bad at algebra. Algebra is the main part and tool of maths, without it most maths doesn't happen. That said, you've presumably only seen GCSE maths as yet, which is incredibly basic compared to degree level engineering maths.
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