I just recently downloaded the TK Combat mod but I can't figure out how to use it. I use the spell and then click the key configuration key and it says press action key but thats where I get lost. I try pressing letters, numbers and f1 - f11 but I don't know if it works or if i'm pressing the wrong key or what. Can someone give me instructions on how to set and then how to use it?

Hate to be that guy; but did you read the mod readme and description?

yes

It's pretty straightforward. Press a direction + activation key. Different directions and weapons trigger different effects.

I did find it easier using a mouse with programmable buttons because it makes pressing one of the WASD keys + the activation key a lot easier.