Are my chances of getting in a top Uni for Computer Science good?

I study A Levels in bio,chem,physics and maths.
In my year 12 end of year exams got A*A*A*A (A was in Chemistry).I have never studied computer science in school before, so I am self teaching basics of python and in a few months will start with Java and I am reading plenty of books from recommended reading list of Oxford University.

I would like to apply for places like Imperial,Cambridge Warwick,UCL...but I dont have further maths nor computer science a levels because I was dumb and it took me time to realize what I wanted to do after a levels...That's why I chose the 4 MOST BROADEST A LEVEL COMBINATION EVER that could lead me to any STEM discipline (only during summer after year 12 I realized that I want to study cs, before that I wanted to either study medicine or engineering or NatSci).

A lack of computer science A level doesn't really matter, not taking FM could be a problem though, definitely for the universities you're listed. I would encourage you to look at entry requirements and see if you can get in touch with any admissions teams to see what they think. However, there are also other good unis for computer science that don't require FM as much. Bath, for example, lowers your offer if you get a certain grade in FM, which suggests that it is nice but not required. Basically, I recommend not closing off your options to only the 'best' or most well known unis because there are other good options

What about kings or qmul? I'd like to preferably stay in London.

I study A Levels in bio,chem,physics and maths.
In my year 12 end of year exams got A*A*A*A (A was in Chemistry).I have never studied computer science in school before, so I am self teaching basics of python and in a few months will start with Java and I am reading plenty of books from recommended reading list of Oxford University.

I would like to apply for places like Imperial,Cambridge Warwick,UCL...but I dont have further maths nor computer science a levels because I was dumb and it took me time to realize what I wanted to do after a levels...That's why I chose the 4 MOST BROADEST A LEVEL COMBINATION EVER that could lead me to any STEM discipline (only during summer after year 12 I realized that I want to study cs, before that I wanted to either study medicine or engineering or NatSci).