If your student visa in Australia or any other category visa has been refused you can file an appeal with the department of home affairs, or the AAT, as the case may be. The visa refusal generally specifies the time for the appeal. Please bear in mind that the appeal must be filed within the specific time frame.
You can file an appeal with the department of home affairs or AAT against the visa refusal through your visa agent or attorney. The agent or agency representing you must be well-versed in every aspect of the Australian immigration requirements and visa application process to successfully represent you and argue your case. This way, you have a higher chance of the refusal being overturned and you receiving a visa.