Replacing wiper blade

I’m trying to replace the original rear wiper blade on my 06 Subaru Outback. How do I get the original one off?

Your Owner’s Manual provides instructions for that, as well as on a wealth of other topics. There is likely to be a small graphic in the manual, showing how to release the blade.

if it is just the rubber replacement type then at one end pull down on the rubber and pull out…replace the same way…

See if any of this helps.