Hey, dunno if you've already found information but I'll give you some anyway! I'm going into my second year of physiotherapy and I study in Scotland.
Your A-levels are perfectly good, you have more than three suitable sciences for the course, you have chosen well! This will also be a huge advantage to you when you reach university.
In terms of what you will be learning in university, all universities throughout the UK will aim the first part of your learning (a year or so) with theory and the fundamental principles of physiotherapy practice. This will be combined with practical sessions with your classmates. You will learn applied physiology, psychology, anatomy, physics,etc. You will know absolutely everything there is to know about human movement in no time! Then you will also have the opportunity throughout the years but especially towards the end of the course to go on placements. You will be amazed at all the different specialities you will be working in. These range from palliative care, neurology, surgical, cardiorespiratory, sports, paediatrics and many more. You will be involved in treating patients undergoing cancer treatment and are unable to do basic human movements such as standing up and walking because their body is being weakened through through their battle with cancer and the effects of their treatment. Or you may be working with young and old individuals who have been paralysed and may or may not regain mobility. Or you may simply be working with a patient who has sprained their ankle! Or perhaps you might work in a surgical ward treating patients who have pain, mobility and breathing problems due to the effects of surgery and the anaesthesia. Its a field full of surprises! You will be able to diagnosis and treat many musculoskeletal conditions and also be able to identify when a problem involves the neurological, cardiac, vascular or many other systems of the body and refer the patient to the right specialist.
As for universities, all universities which offer physiotherapy are accredited and validated by the HCPC (physiotherapist's governing body) so don't worry about the best because they all have met the standards to offer the course. However, as most of your learning will come from working in a hospital, perhaps you should choose a university which is affiliated with a teaching hospital as you won't have any problems finding placements and you may also have lectures and classes in the hospital.
I hope I have helped and I wish you all the best in your A-levels! When you get into physiotherapy, you will be thinking "waw A-levels was nothing!".