A small business (not a profession) with turnover up to ₹2 crore — ₹3 crore if cash receipts are ≤5% — can declare 8% of turnover (6% for digital/bank receipts) as income under Section 44AD, with no books and no audit, filing ITR-4.
Under presumptive you don't file full accounts, but ITR-4 asks for a few summary figures as on 31 March — total debtors, creditors, stock-in-trade, and cash + bank balance. Enter your actual bank and cash balances; they don't drive the tax (income is the % of turnover), but they should be genuine.
If you opt into 44AD, you should continue for 5 years. Opting out earlier (declaring lower profit) means books + audit for the next 5 years if your income exceeds the exemption.
Professionals use Section 44ADA; transporters use Section 44AE.