This is a very basic macro, but its just to let you get an idea on how to make the macro

/assist main main=your main character who will be doing the targeting.
/cast fireball easiest way to do this is type /cast then open your spell book and shift click the spell you want to use.

You can also make another macro and have it do \cast icearmour (if that’s what its called.)

Just remember and put /cast before a spell.

If you want multiple spells do /cast /stopcast

For example:

/cast combustion
/stopcast
/cast fireball

Anyway these are totally the most basic macros you can make.