If you're under the tax bracket of 38,000. Why am i getting taxed 15% when it should be 5%

The Federal tax rate is 15% on your first $45,282 of taxable income.

Provincial Tax rates vary, but in some provinces it is close to 5% on the first tax bracket. Ex: In Ontario, the rate is 5.05% on the first $42,201 of taxable income.

https://turbotax.intuit.ca/tips/an-overview-of-federal-tax-rates-286

https://turbotax.intuit.ca/tips/canada-tax-federal-and-provincial-tax-tax-brackets-and-due-dates-141