You can only apply for a Temporary Skill Shortage (subclass 482) visa if you have a sponsor who nominated you for this visa. Your sponsor must provide evidence of having a genuine need to fill in that position with an overseas worker.
There are three streams for Temporary Skill Shortage (subclass 482) visa.
You can apply for the labour agreement stream if your sponsor is a part of the labour agreements. The labour agreements represent an accord between Australian employers and the Australian government that allows businesses to bring workers to Australia according to the specific labour agreements. Your occupation must be included in the labour agreements between the Government of Australia and your sponsor. Your sponsor must be a part of the labour agreements.