For C: I would recommend you just get a newer CPU since i7-7700K is getting a bit old. Not a bad cpu but I wouldn't pair it with a 1070 Ti.A. What temperature does your CPU reach during gameplay?
B. I sincerely doubt overclocking it would "destroy it." CPUs can take a lot of heat for an extended period of time. In modern thin and light laptops, it is not unheard of for i5 and i7 processors to hit almost 100 C when running CPU intensive tasks for a long period of time.
C. If your CPU temps make you uncomfortable, you should upgrade your CPU cooler to give you the headroom to overclock.
For C: I would recommend you just get a newer CPU since i7-7700K is getting a bit old. Not a bad cpu but I wouldn't pair it with a 1070 Ti.
Can't really upgrade, don't have the money for it, i really want a solution to this T_T.