At the time the book of Revelation was written the Apostle John was the last of the original disciples and miraculously survived being boiled in oil only to be banished to a deserted Greek Island called Patmos to die with the scorpions. God saved John so He could show John the future just for you. Jesus, in His glorified body, appears to John and shows John visions of the 21st century. John describes what he sees using his 1st century knowledge. You need to place yourself in his position to understand what he was seeing.
The first three chapters of Revelation Jesus is showing John a glimpse of heaven and giving messages to the seven churches of Asia Minor or present-day Turkey. These messages are also relevant to believers today. The overall message is to “keep the faith” or “go back to your first love”. Hold fast to the faith that believes the Blood of Jesus Christ alone pays for your sin. The Spirit of God who resides in you (1 Corinthians Ch.6) will guide you into all truth.