Your other income will be taxed the same way it always has been. Your Social Security may be taxed, depending on how much other income you have and your filing status. If your salary is a good on, expect your SS to be between 50 and 85% taxable (it's a strange calculation).
But yes, you can receive both salary and SS. Since 66 should be your full retirement age, you do not have to worry about repaying any of the SS received.

