Daniel was given a prophetic secret with seven "Do Not Open Until Christmas" seals because the fulfillment of those prophecies was still a couple of hundred years away:
[Dan 12:4 NLT] (4) But you, Daniel, keep this prophecy a secret; seal up the book until the time of the end, when many will rush here and there, and knowledge will increase."
Right on Daniel's timeline/agenda given in his prophecies the Messiah appeared to fulfill all of prophecy. Those things written in the scroll concerned the LORD's Day (the first 70 years of the first century). For thousands of years God had promised that Israel's end would one day come with horrific judgment from God. The angel tells Daniel that in the seven (7) years of tribulation that "shatters the holy people" EVERYTHING predicted will have occured:
[Dan 12:6-13 NLT] (6) One of them asked the man dressed in linen, who was now standing above the river, "How long will it be until these shocking events are over?" (7) The man dressed in linen, who was standing above the river, raised both his hands toward heaven and took a solemn oath by the One who lives forever, saying, "It will go on for a time, times, and half a time. When the shattering of the holy people has finally come to an end, all these things will have happened." (8) I heard what he said, but I did not understand what he meant. So I asked, "How will all this finally end, my lord?" (9) But he said, "Go now, Daniel, for what I have said is kept secret and sealed until the time of the end. (10) Many will be purified, cleansed, and refined by these trials. But the wicked will continue in their wickedness, and none of them will understand. Only those who are wise will know what it means. (11) "From the time the daily sacrifice is stopped and the sacrilegious object that causes desecration is set up to be worshiped, there will be 1,290 days. (12) And blessed are those who wait and remain until the end of the 1,335 days! (13) "As for you, go your way until the end. You will rest, and then at the end of the days, you will rise again to receive the inheritance set aside for you."
[Rev 22:10 NLT] (10) Then he instructed me, "Do not seal up the prophetic words in this book, for the time is near.
[Luk 21:20-24 NLT] (20) "And when you see Jerusalem surrounded by armies, then you will know that the time of its destruction has arrived. (21) Then those in Judea must flee to the hills. Those in Jerusalem must get out, and those out in the country should not return to the city. (22) For those will be days of God's vengeance, and the prophetic words of the Scriptures will be fulfilled. (23) How terrible it will be for pregnant women and for nursing mothers in those days. For there will be disaster in the land and great anger against this people. (24) They will be killed by the sword or sent away as captives to all the nations of the world. And Jerusalem will be trampled down by the Gentiles until the period of the Gentiles comes to an end.
In complete agreement with the angel in Daniel's prophecy Jesus says:
[Luk 21:27-33 NLT] (27) Then everyone will see the Son of Man coming on a cloud with power and great glory. (28) So when all these things begin to happen, stand and look up, for your salvation is near!" (29) Then he gave them this illustration: "Notice the fig tree, or any other tree. (30) When the leaves come out, you know without being told that summer is near. (31) In the same way, when you see all these things taking place, you can know that the Kingdom of God is near. (32) I tell you the truth, this generation will not pass from the scene until all these things have taken place. (33) Heaven and earth will disappear, but my words will never disappear.
So Daniel's scroll contained the end of Israel as a holy nation. It was sealed up until the time of the Messiah and the LORD's Day. In Revelation the seals are opened, the judgments unleashed and the cataclysmic end of the KOSMOS (the old covenant, temple-based, Jerusalem based theocracy) and the arrival of the kingdom of heaven/God aka the new Jerusalem aka the body of Christ.