Getting into 'any good career' is a fairly broad target! If you want to keep your options open however, doing a selection of 'hard,' non-vocational A levels is a good idea.
Generally speaking, the more people that find a subject difficult the more value it is deemed to have. Maths and the hard sciences (Physics, Chemistry, Biology - usually in that order) are what are considered 'hard' by most people and, subsequently, have a lot of value. To keep the door open to 'any good career' however, it might be wise to include a non hard-science subject that would broaden your skills base. A humanities or social science subject would certainly do this, economics being one example, and this would be useful to many potential careers.
In terms of a future career it is also important to consider aptitude; if you make it to the top in any field you will have a good career and you will maximise your chances of doing so if you pursue a career which aligns with your aptitudes. Thus, selecting A levels in subjects you have an aptitude for is also a good strategy. If you're not sure what you have an aptitude for then think about what you find genuinely interesting - they often align.
In short, a good strategy to meet your goal of getting into any good career would be to choose subjects at the confluence of 1.what subjects are high-value 2.what you have aptitude/interest for 3. what keeps the door open to a variety of possibilities.
My selection would be: Maths, Economics, Chemistry.
Best of luck.