You propably meant binding f9 to wheel buttons, you can do it in game too. Open controllers menu and pick either ctrl+ or alt+ tab, type /press F9 into one of the bind slots, next to it on right you can bind a controller button for this command.
this takes away 1 slot for binds so i recommend to put it to something you never use like alt+f12. check screenshot for example
Yeah, it's quite simple works with every character from 0-9, A-Z and F1-F12, i dont know if they work with page up/down, etc.
You can also bind combinations with it too, say you want something like shift+f for your wheel buttons. The command for these are a bit different, they start with "/shift" instead of /press (so the command for shift+f is "/shift F"), same thing applies for combinations that need alt or ctrl (they use "/alt" and "/ctrl" respectively).
For example, altough Alt + F4 is defined in the control settings, you can still make it a separate command /alt F4.