From my 1995 Chevy Blazer, I need to drain my transmission fluid?

yes you need to drop the pan to get the oil out.so loosen the bolts all the way around the pan and tank out enough to the bolts at one corner and pry the pan down so you can drain some fluid out.but the gasket may leak once you tighten it back up and you may need to drop the whole thing and put a new gasket in if it does leak.its not hard just a very messy job get some floor dry and keep handy you will need it.