I have a problem with my car overheating, and a shifting problem, can they be linked together??? I went to go check my fluid levels and my transmission has way too much in there, don't know how or why

These cars have a big problem with upper and lower intake gaskets, causing loss of coolant, oil in coolant, etc. I can't see that getting into the transmission, but your trans cooler lines do run into the radiator, it's an 'in-rad' cooler, where it is surrounded by coolant. Trans lines are under higher pressure so generally if there is a leak, it's trans fluid into the radiator, not coolant into the trans. The rubber trans lines also tend to leak, especially at the clamp, in that case it just goes on the ground. Did someone just overfill the trans? Can you determine if it is trans fluid only? I really can't see coolant getting into a tran via trans cooler lines. How does the coolant in the radiator look? Try some NAPA block tester, and see if you are getting exhaust gases in the coolant, that is an indicator of a bad head/intake gasket. Another source of coolant loss, assuming it is not from leaking hoses, is the water pump, it can leak from the shaft if it is worn. You say coolant is puddling 'near the transmission,' although that doesn't guarantee the leak is back there (it can run along lines/engine/frame), it's still a good place to start leaking for your coolant leak - heater hoses, intake gasket, freeze plug, check the trans cooler lines haven't cracked at the radiator, etc. You need to address this asap, if coolant is getting contaminated it can't keep engine cool, if oil is getting contaminated it can't provide lubrication and bearings could fail. Good luck