I am planning on making a witch with the plague patron(Plague: 2nd—detect undead, 4th—command undead, 6th—contagion, 8th—animate dead, 10th—giant vermin, 12th—create undead, 14th—control undead, 16th—create greater undead, 18th—energy drain.), but I don't understand how these spells work (i.e. how many undead total I can have, using all of my abilities). I have read a few guides but they all say that plague is a terrible patron because you can't control the undead, but isn't that what command/control undead does?
I have a cool concept for the character rp wise, but I have never made a character like this or a spellcaster. Does having undead servants require me to have an evil alignment?