I'll still recommend Keyclone for a first time boxer.
It's very basic, but quite powerful as a keyboard broadcast option.

Just blacklist a few things, like Num Lock and Tab.
And remember to use the Pause Key, when chatting.

Anything you press, the others all receive.
But you don't necessarily need to have an ability on that keybind for all accounts.
So the healer might have heals on four keybinds, where the others have nothing on those keys.

Down the road, or immediately if you don't mind a steeper learning curve.
I'd strongly recommend Inner Space.
There are a lot of things you can do with it, which Keyclone cannot.
It has a wizard too, so from start to playing isn't that much longer.
But configuring your interface to do exactly as you'd like (tinkering with it) has a bit of a learning curve.

Whatever you go with, the community has good support.
Don't be afraid of asking questions.
But remember there are wiki's and sticky posts with a ton of good info too.