Unless exempt from undertaking an English test, (see below for exemptions), the Student Visa requires you to do one of their specified English tests.
Full information is available at https://immi.homeaffairs.gov.au/help-support/meeting-our-requirements/english-language/competent-english
The Australian Civil Aviation Safety Authority (CASA) also has its own English requirements that are different to the Student Visa requirements (see below for CASA exemptions)
If you do need to do an English test, its important to choose the best test that satisfies both the Student Visa and CASA requirements.
IELTS is the best option to satisfy both Student Visa and CASA requirements
TOEFL iBT can be effective – if you score 71+ then all requirements are satisfied but if you score 64-70 you will meet student visa requirements but still need to be assessed on arrival by a CASA approved assessor,
Pearson, Cambridge English and the Occupational English Test (OET) are okay for the Student Visa however to meet CASA requirements you would need to be assessed on arrival by a CASA approved assessor.
Note: Your assessment with a CASA approved assessor will result in an ICAO (International Civil Aviation Organisation) English Language Proficiency Level of between 1 and 6. The minimum required is Level 4 (a Native Speaker would usually be Level 6). You should be confident that if you achieve any of the test results outlined below, that you should achieve at least Level 4.