1968 kenmore sewing machine

Question

I just got a Kenmore sewing machine model 158.18010. The motor works when you turn it on....but it does not move the belts. I can manually move the flywheel.....but with the belts in place, it is extremely difficult. If the belts are removed, the flywheel does move the needle up and down. Do you think the first thing I should try is to get new belts?