You do not need any points to apply for a normal Australian visa. However, if you are applying for a permanent residency visa, you will require at least 65 points out of 100. These are dependent upon your educational qualifications, age, English proficiency, work experience, etc.

The possibility of extension depends upon the visa. For a visitor visa, you will not be allowed to extend. You will have to apply for a new one once your current visa expires. However, for a student visa, you may be allowed to extend it by applying for another type. For a permanent visa type, you do not need to extend the, as they have an indefinite validity.

Yes, this will definitely affect your visa application and will likely be rejected. It is necessary to ensure that the name in all the documents is the same as the one in the passport. However, if this difference is due to a name change, you will need to provide evidence suggesting the same. In this case, your application will be unaffected by it. It is extremely crucial to provide accurate documents.