You can be fired as an Australian employee at any time but they will still need to pay out the notice period in their contract and whatever accrued annual leave they had.
Most notice periods in AU are 4 weeks so you either are fired with 4 weeks notice or fired immediately and paid for those 4 weeks.
(The notice period also applies if you decide to leave the organisation)
The rule specifically is:
Can notice be paid out instead of worked?
Yes. An employer can either:
Let the employee work through their notice period, or
pay it out to them (also known as pay in lieu of notice).
If the employer pays out the notice, the amount paid to the employee must equal the full amount the employee would have been paid if they worked until the end of the notice period. This includes:
incentive-based payments and bonuses
loadings
monetary allowances
overtime
penalty rates
any other separately identifiable amounts.
If the employer pays out the notice, the employee does not accrue any annual leave for the notice period they were paid out for.
https://www.fairwork.gov.au/ending-employment/notice-and-fin...