Section 44ADA provides a presumptive taxation scheme for professionals where 50% of your gross receipts from profession are treated as your income. The section can be opted only if you have gross receipts up to Rs 50 Lakhs in previous year. Further, you are not allowed to claim as deduction any of the business expenses which you incurred.
However, if you do not opt for 44ADA, you would be taxed as per the normal provisions of Income Tax Act 1961 and would be allowed to claim for deduction of all expenses related to your profession.
You can make an assessment in both the scenarios and opt for one which is the most beneficial to you. Following is the link to the complete guide of Section 44ADA of Income Tax Act, 1961.