The "seven spirits of God" are mentioned in Revelation 1:4; 3:1; 4:5; and 5:6. The seven spirits of God are not specifically identified, so it’s impossible to be dogmatic. Revelation 1:4 mentions that the seven spirits are before God's throne. Revelation 3:1 indicates that Jesus Christ "holds" the seven spirits of God. Revelation 4:5 links the seven spirits of God with seven burning lamps that are before God's throne. Revelation 5:6 identifies the seven spirits with the "seven eyes" of the Lamb and states that they are "sent out into all the earth."
[Rev 1:4 NKJV] 4 John, to the seven churches which are in Asia: Grace to you and peace from Him who is and who was and who is to come, and from the seven Spirits who are before His throne,
[Rev 3:1 NKJV] 1 "And to the angel of the church in Sardis write, 'These things says He who has the seven Spirits of God and the seven stars: "I know your works, that you have a name that you are alive, but you are dead.
[Rev 4:5 NKJV] 5 And from the throne proceeded lightnings, thunderings, and voices. Seven lamps of fire [were] burning before the throne, which are the seven Spirits of God.
[Rev 5:6 NKJV] 6 And I looked, and behold, in the midst of the throne and of the four living creatures, and in the midst of the elders, stood a Lamb as though it had been slain, having seven horns and seven eyes, which are the seven Spirits of God sent out into all the earth.
There are at least three possible interpretations of the seven spirits of God. The first is that the seven spirits of God are symbolic of the Holy Spirit. The Bible, and especially the book of Revelation, uses the number 7 to refer to perfection and completion. If that is the meaning of the “seven” in the "seven spirits," then it is not referring to seven different spirits of God, but rather the perfect and complete Holy Spirit. The second view is that the seven spirits of God refer to seven angelic beings, possibly the seraphim or the cherubim. This would fit with the numerous others angelic beings that are described in the book of Revelation (Revelation 4:6-9; 5:6-14; 19:4-5).
[Rev 4:6-9 NKJV] 6 Before the throne [there was] a sea of glass, like crystal. And in the midst of the throne, and around the throne, [were] four living creatures full of eyes in front and in back. 7 The first living creature [was] like a lion, the second living creature like a calf, the third living creature had a face like a man, and the fourth living creature [was] like a flying eagle. 8 [The] four living creatures, each having six wings, were full of eyes around and within. And they do not rest day or night, saying: "Holy, holy, holy, Lord God Almighty, Who was and is and is to come!" 9 Whenever the living creatures give glory and honor and thanks to Him who sits on the throne, who lives forever and ever,
[Rev 5:6-14 NKJV] 6 And I looked, and behold, in the midst of the throne and of the four living creatures, and in the midst of the elders, stood a Lamb as though it had been slain, having seven horns and seven eyes, which are the seven Spirits of God sent out into all the earth. 7 Then He came and took the scroll out of the right hand of Him who sat on the throne. 8 Now when He had taken the scroll, the four living creatures and the twenty-four elders fell down before the Lamb, each having a harp, and golden bowls full of incense, which are the prayers of the saints. 9 And they sang a new song, saying: "You are worthy to take the scroll, And to open its seals; For You were slain, And have redeemed us to God by Your blood Out of every tribe and tongue and people and nation, 10 And have made us kings and priests to our God; And we shall reign on the earth." 11 Then I looked, and I heard the voice of many angels around the throne, the living creatures, and the elders; and the number of them was ten thousand times ten thousand, and thousands of thousands, 12 saying with a loud voice: "Worthy is the Lamb who was slain To receive power and riches and wisdom, And strength and honor and glory and blessing!" 13 And every creature which is in heaven and on the earth and under the earth and such as are in the sea, and all that are in them, I heard saying: "Blessing and honor and glory and power [Be] to Him who sits on the throne, And to the Lamb, forever and ever!" 14 Then the four living creatures said, "Amen!" And the twenty-four elders fell down and worshiped Him who lives forever and ever.
[Rev 19:4-5 NKJV] 4 And the twenty-four elders and the four living creatures fell down and worshiped God who sat on the throne, saying, "Amen! Alleluia!" 5 Then a voice came from the throne, saying, "Praise our God, all you His servants and those who fear Him, both small and great!"
A third possibility is based on Isaiah 11:2, which says, “The Spirit of the LORD will rest on him — the Spirit of wisdom and of understanding, the Spirit of counsel and of power, the Spirit of knowledge and of the fear of the LORD.” This could possibly explain the seven spirits of God: (1) Spirit of the LORD, (2) Spirit of wisdom, (3) Spirit of understanding, (4) Spirit of counsel, (5) Spirit of power, (6) Spirit of knowledge, (7) Spirit of the fear of the Lord. The Bible doesn’t tell us specifically who/what the seven spirits are, but the first interpretation, that they are the Holy Spirit, seems the most likely.
[Isa 11:2 NKJV] 2 The Spirit of the LORD shall rest upon Him, The Spirit of wisdom and understanding, The Spirit of counsel and might, The Spirit of knowledge and of the fear of the LORD.