1993 Chevy Astro

If none of the power windows work? Check the power window circuit breaker, also use a testlite and see if there is voltage on that circuit, with the key on. Even if any fuses and or circuit breakers are good, if there is no voltage on the circuit, the circuit is dead.

As far as the hvac, are you saying the blower won't even blow, or the air is not cool?

thanks for the reply about my window as far as the air conditioner its not coming on at all these are the things that happen all in one day my transmission wouldnt change gears it wouldnt catch second gear then my window wouldnot go up nor down and the air conditioner wouldnt come on and the speedometer was register the speed amount i since then ive replace the transmission and still having the same problem

Make sure the battery has a full charge and the battery connections are all clean and tight. The feed circuits for both the hvac blower motor and power windows goes hot when you turn on the key. If those circuits aren't hot, I"d have to check the feed to and from the ignition switch.