The following is from thewestminsterstandard.org:
Q. 6. How many persons are there in the Godhead?
A. There are three persons in the Godhead; the Father, the Son, and the Holy Ghost; and these three are one God, the same in substance, equal in power and glory.
Q. 7. What are the decrees of God?
A. The decrees of God are, his eternal purpose, according to the counsel of his will, whereby, for his own glory, he hath foreordained whatsoever comes
to pass.
Q. 8. How doth God execute his decrees?
A. God executeth his decrees in the works of creation and providence.