Good Morning,
I am confined to a wheelchair and only have partial use of left hand and arm making it extremely slow and difficult to type. I am wanting to reassign the function keys(which I never use)to output the same phrase again and again. Kind of like office clipboard with no need to copy each time. Is this possible, and if so, how would I do it ?

Here's a Google search for macro software, which I think is what you're looking for. Some are free and some aren't; it mostly depends on exactly what sort of features you're looking for.

There are also keyboards that let you make keyboard macros and assign them to dedicated keys, if you're interested in that route.

Just out of curiosity, have you considered a dedicated one-handed keyboard? Take a look at http://www.frogpad.com/. I've thought about getting one so I don't have to move my hands from the keyboard to grab the mouse, but they're also advocated by some disability organizations.

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