My car will not go into second gear coming down from third, but it will go into second gear from first gear.
From the information provided on your Chevy Camero, it appears that you need to adjust the Throttle Valve (TV) cable. This TV cable on your Chevy Camaro controls hydraulic line pressure, the shift points, the shift feel and throttle downshifts. Therefore, if the TV cable is not adjusted properly, it can cause numerous transmission problems. I recommend enlisting the assistance of a certified mechanic, such as one from YourMechanic, to come by and test drive your Camaro. They will have the experience needed to quickly determine if a simple adjust is what your Camaro needs and make those adjustments so your Camaro can shift without problems.