1. What is reason for providing this service from India if you are situated in Australia?
2. Without registering a company or any entity I don't think it is possible to provide such service from India as you are situated outside India.
3. Yes you can collect amount in NRO account. Regular taxes at slab rate needs to be paid.
4. First you need to plan what kind of entity you want to open in India.
5. Other than the taxes mentioned in point 3 of question as of now no other tax is there.
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