A statutory audit under the Companies Act reports to the members on whether the financial statements give a true and fair view. A tax audit under section 44AB reports to the tax department, in Form 3CD, specified particulars (method of accounting, stock, loans, TDS, GST reconciliation, and the rest). A company may need both; a proprietorship never needs a Companies Act audit and may still need a tax audit. Form 3CA is used where a statutory audit already exists; Form 3CB where it does not. See statutory audit and tax audit.
Answer
How does a tax audit differ from a statutory audit?
Different statute, different report, different addressee — and many companies need both.