Partner visa (subclass 820) is designed for overseas citizens who are in a relationship with an Australian citizen, permanent resident or eligible New Zealand citizen to live in Australia temporarily.
There is a 2-stage process which leads to permanent residency. The Partner visa (subclass 820) is the first step of the partner visa application which you can apply for this visa based on marriage or de facto relationship.
You should be in Australia when you apply for this visa as this is an onshore application.
Before you apply for this visa, you have to meet the minimum requirements for this visa.