Hi Pentactle, There are many different accents and ways of pronunciation both in the USA and in the UK (and of course in Scotland, Ireland, South Africa, Australia and New Zealand). So standard pronunciation does not really help so much. The best thing you can do is to expose yourself to these differences by listening to as many different kinds of spoken English as you can, by listening to songs, podcasts, movies etc and noticing the differences. For example, even though I am an English speaker from London I only recently learned the difference between Canadian and American English by listening carefully. You might find this video fun to start with: https://www.youtube.com/watch?v=3UgpfSp2t6k

bbc上就有British English发音的教程

Yes, we do use IPA symbols. In fact, the answer is in the name: INTERNATIONAL Phonetic Alphabet. The whole point of the IPA is that it is not region-specific or even language-specific - the phonetics of any language or language variant can be transcribed using IPA symbols. If you use any good dictionary ( such as Oxford, Cambridge or Collins), you will see words transcribed in IPA symbols in both standard British English pronunciation and standard US pronunciation, so that you can compare. The online versions also have an audio facility whereby you can listen to the words pronounced in both accents.