You shouldn't have a problem getting into most colleges/sixth forms to do history and/or geography if you have a decent grade in another essay based subject, particularly English Lit. However, I would say the best advice, and I wish someone had said this to me, is to keep your options open and well rounded, especially if you're not sure what you want to do in future. For example, take an art/practical subject, essay based subject and a science.
I would also add that if you're not 100% on going to university, A-Levels are not the be all and end all. They are a huge jump from GCSE in my experience and are challenging and stressful to the point where I would advise not taking them unless you are sure you want to pursue higher education. But again, in keeping your options open, it may be a good choice for now. Good luck!