how do i seen auxiliary on mission/ bring the on missions. lv them up?

i did read the in game tutorial but it didn't rely help much and left be wandering for hours how to use them. can some give me a short, straight to the point explanation on how auxiliary work?

You need to send them on gathering missions, such as the ones from the cafe. Unlike you, auxiliaries will change their class automatically based on the weapon you give them.

how you unlock it? and even break down stuff in your own room like the jp pso2