Payoneer deducts an amount when I withdraw to my bank. Is that tax?

No, that deduction is not tax; it is the platform's withdrawal fee and the bank's charge. Tax is calculated on your annual earnings, not on the amount withdrawn, and it is paid through your return. Those charges can be deducted as business expenses to the extent they relate to the work. To make that case you need to keep the withdrawal summary and the bank receipt together; without both, the amount can neither be expensed nor matched to income.