Not really, no.
There are many regional variations in accent throughout the UK, and quite a few less-pronounced variations in Australia. The only real similarity they have is that the Australian accent is completely non-rhotic (unlike the USA) and a large number of UK regional dialects are non-rhotic.
Australians do not speak in a peculiar cockney accent. Australian English has its own distinct accent and dialect that has evolved since the first settlement of the country. While there may be some similarities due to historical connections with England, Australian accent is influenced by a variety of factors including Indigenous languages, immigrant communities, and isolation from the UK.
It isn't.Australians speak English. Although not the official language (Australia does not have an official language), English is the default language throughout the country. Australian English follows the same spelling patterns as UK English, rather than American English.
UK
English!
An Australian in the UK can get car insurance from the same insurers where UK residents get their insurance from.
No, it has more of an accent.
Make the UK your home. And remember that the UK is the home of hundreds of distinct accents, dialects and regional vocabularies, so your question is a bit vague. Otherwise, if this is for performance (i.e., you are an actor wishing to perfect your accent) there are coaches who specialize.
No. Australian English and UK English are essentially the same, with regional differences. For example, the regional differences in English in the UK are more pronounced than those in Australia, but there are certainly some regional differences win Australia. In addition, some of the unique slang terms in UK and Australian English differ, largely as a result of other cultural influences within the two countries.
No.
A UK 30E will be the same as an Australian 8E.
British is not a language, but rather a term used to describe people or things from the United Kingdom. The British accent refers to the way English is spoken in the UK, but English is the language spoken in the UK.
In the UK, people primarily speak British English, which has variations in accent and vocabulary depending on the region. American English is not typically spoken as the primary language in the UK.