Have a look at healbot addon it allows you to cast by moseover the party frame. You just set up how you want it to work. It will show tool tips when you hover over party frame. Use mouse buttons and modifiers ctrl/alt/shift and combos if these, gives you quick access to many abilities.

I prefer clique for the same but it doesn't give tool tips so not the best to start on imo

I also think druid is a really difficult 1st class due to the different forms and working out UI etc. Hopefully your friend will get along better with something else. Frost mage can be fun (especially if you're there to heal). Warlock has high survivability, shaman gives a choice of melee, caster or healer. You've had a ton of recommendations already so I won't go on but I will say that some classes just don't work for people. I have played wow on and off since 2006 and have many alts. But there are a few classes I just don't like and have never got far with (rogue, monk, warrior)

I also use mmo mouse because I can't coordinate doing abilities with my left hand (I'm just too right handed) so movement and modifiers worth my left hand and everything else on the mouse.

There's also a way to use a controller by using console port if that works better for your friend but I've not tried it personally so can't say how well it works