Can i get into Cambridge or Oxford when im doing foundation in Maths and Science

By all means try, but please be aware that weakness in maths at GCSE level may have some negative impact on the assessments made by universities of your overall academic achievement and potential.
As for lawyering, I am not especially numerate myself, but I did OK in what were then called the O levels in maths and physics, many thousands of years ago. Although I am far from being any sort of maths or science whizz, I find that a moderate familiarity with not very advanced maths is sometimes useful in my work as a lawyer dealing with commercial disputes. I sometimes get dizzy reading the expert reports of accountants, economists, and valuers, but I can make it through.
The ability to understand a set of company accounts isn't hard to achieve, but it can be important to legal work, whether transactional or contentious. Personal injury lawyers and family lawyers (I am neither of those) sometimes have to juggle with numbers. Criminal lawyers may not have to do so, unless working on complex white collar fraud cases. Even a public lawyer might sometimes need a bit of maths in order to explain to a Judge why the Secretary of State for Something has or has not made an unlawful decision about the allocation of public resources, the award of a franchise or licence, and so on.
I think that pushing hard to improve your maths might assist, long term, in your academic and career aspirations. When I did my A levels, I realised that I would need Latin for my intended path as a student of history. I had dropped Latin at O level, so I obtained a Latin O level whilst doing my A levels, and that helped me get into Oxford (which at that time tested language skills during the admission process). It also helped during my history degree (for which I needed to use two languages), and each of Latin and French still help a bit in my day job.
I mention this in order to ask: might it be possible to take a maths GCSE alongside three essay-based A levels if you can manage the extra workload? I am thinking not so much about what university you might get into as about potential longer term benefits.
Good luck!

My maths is alright but my eng is much better do u think i still have a chance tho of getting in even though it is so highly recommended

I don't think that I or anyone here can express a reliable view on whether you have a chance of getting into Oxford, as that depends on your overall academic profile, including how well you could do in any relevant aptitude test and whether you could do well in two or more quite challenging interviews. Your teachers may be able to give you some useful guidance. It's great to aim high, but please remember that the process is very competitive, that there are many good universities in the UK, and that you can apply to five universities. It should go without saying that not getting into Oxford doesn't make a person a failure, but some media convey that false impression.
If you haven't already seen the youtube videos about the Oxford admission process made by a Fellow of Jesus College, Oxford, those videos are worth a look.