Unless you're completely focused on doing a Medicine/Engineering or other Sciencey/Maths degree, your A level subjects do not matter (assuming that they aren't "blacklisted" subjects). History/English/Philosophy are all BA degrees meaning that they open a lot of avenues (unlike BSc), however, to travel down those avenues requires a lot of commitment. Journalism instantly pops into my mind, but there are other options like: Teaching, Academia, Law, Politics, Foreign Office, Civil Service and many others.
I wouldn't recommend entering A levels and concerning yourself with how your subjects will determine your later life. The top paid Lawyer in the UK studied Medieval History at undergraduate level. A levels are meant to be a stepping stone for finding a subject that you enjoy - again - unless you are focused on Medicine or Engineering, your A level choices do not matter and what you do after Uni is completely up to you.
Don't worry about it, just focus on doing well at A-levels so you can set yourself up for a successful career after Uni. One step at a time.