I am a night elf who switches between dual wielding destruction magic and using sword plus a shield.

So I had a couple questions:

1) What is most useful between illusion, conjuration, restoration, and alteration? I don't want to spread perks throughout all of them so I only wanted to focus on one.

2) Is it worth adding perks into archery if I have already primarily been using destruction and one handed for combat?

3) What do you think are the most useful skills to put perks into for my play style, or just general play style?

Sorry if some of the questions are really stupid or do not make much sense...in new to TES and role playing games haha

3.One hand Dual wielding perks, Destruction perks and maybe little blocking and the one with elem?ntal protection shield thing.