Software developer/engineer

I'm trying to get into the I.T field in the UK. I'd like to get into software programming engineer/developer.

A little bit of a background about me. In college I did National BTEC in I.T practitioners and I currently have a grade C equivalent function skills for maths and English. I've also built my computers I've also recently done the Comptia A+ and passed.

I'm currently looking into Computer Science IGCSE (Cambridge) or maybe an A level. Would this be viable way of me getting into software programming or is there a better way I can do this?