I urgently need you to check if all my corrections are OK. Thank you very much in advance.

1) The Elizabethan thetre was made up of three different galleries and three kinds of stages (it was made up of three stages surrounded by three tiers of galleries).
2) The firstly was the apron stage where most of scenes took part.
Correction: the main stage was the apron stage where most of the action took place.
3) At its back there was the inner stage. It consisted in a small stage used to represent for instance the witches' cave or Juliet's tomb.
Correction: At its back there was a second stage, the inner stage, used to represent smaller scenes such as the witches' cave in Macbeth...
4) James I believed that witches existed. In his opinion they were almost always women, were often old and had familiars, animal-shaped spirits who helped them do their magic.
5) They made models of their victims in wax and put spells on them.They were also able to foretell the futre, cast spell (repetition) and talk with spirits (better: call up spirits).
6) In the third act they prophesy to Macbeth that no man born of woman will hurt him and that he won't be defeated until Birnam Wood moves to Dunsinane Hill to fight against him (better: as long as Birnam Wood doesn't move to Dunsinane Hill to fight ......)

1. "firstly" -- ? Just use "first."

2. OK

3. Correction is good.

4. comma needed

5. check spelling, "cast spells" (plural)

6. comma needed