I would say the majority of commentaries would say that Daniel 2 and Daniel 7 are describing the same succession of kingdoms - but using different symbols.
Every time I read through these two chapters and compare them, I become less and less convinced that this is the case.
In Daniel 2, we see a statue that is composed of 4 distinct parts: head of gold, breast and arms of silver, belly and thighs of bronze, legs of iron and feet mixed of iron and clay.
It is generally agreed that the first three kingdoms of Daniel 2 are identified as the Babylonian followed by the Medo-Persian, followed by the Greek (Macedonian) kingdom. There are some disagreements as to the identity of the fourth kingdom. At present, the majority view is that this fourth kingdom is Roman. The minority view is that this kingdom is referring to the Islamic Caliphate. I believe the latter case to be true. You can read about the explanation for that here:
Both of these chapters are written by Daniel in Aramaic. Chapter 2 is describing the dream of King Nebuchadnezzar and the interpretation of that dream. The king himself is identified as the head of gold.
You are that head of gold.
Notice the wording describing the kingdoms that follow - "after you, there will arise".
But after you, there will arise another kingdom, inferior to yours. Next, a third kingdom, one of bronze, will rule the whole earth. Finally, there will be a fourth kingdom as strong as iron...
It's pretty clear that these kingdoms follow one another - with the fourth kingdom being the last one before the kingdom of God is established on earth (Dan 2:35, Dan 2:44-45).
Daniel 7 describes Daniel's vision and interpretation of four beasts that arise from the earth. This dream occurred during the reign of Belshazzar - Nebuchadnezzar's son or grandson. He was the last Babylonian king to rule the throne before the Persians conquered the kingdom. The Babylonian kingdom was coming to a close. And yet Daniel uses the same words "will arise" when describing when these kings appear:
These great beasts, which are four in number, are four kings who will arise from the earth.
Nebuchadnezzar was gone by this time and the Babylonian kingdom was coming to a close - yet in the interpretation of this vision it clearly states that these 4 kings "will arise" - future tense. Some will argue that the wording "will arise" is not a correct translation opting for "four kings that rise up from the earth" - removing the future tense. But this is not the only contradiction.
Notice Daniel's description of how they appear:
And four great beasts were coming up from the sea, different from one another.
Noticeably absent from the description of these beasts and in the interpretation is wording suggesting that these are successive kingdoms that follow one another - each replacing the previous. The language of these verses seem to imply that these four beasts are contemporaries of each other. They seem to come up together.
There is an order in which they are described. But this does not imply that they are four successive kingdoms. In fact other verses in this same chapter describe the fourth beast as "devouring, crushing and trampling" the other beasts - they appear to be all present at the same time with the fourth beast prevailing over the three others.
It devoured and crushed and trampled down the remainder with its feet.
Then I desired to know the exact meaning of the fourth beast, which was different from all the others, exceedingly dreadful, with its teeth of iron and its claws of bronze, and which devoured, crushed and trampled down the remainder with its feet.
It seems to me, that there may be a bit of shoehorning that takes place to fit the two chapters together. I don't think a person can be dogmatic about this. Presumably, one would expect that this final beast/kingdom would experience opposition at the end of the age. Could Daniel 7 be describing this opposition? This chapter could be describing a clash of kings/kingdoms - where the fourth king prevails over the other three.
The fourth beast will be a fourth kingdom on the earth, which will be different from all the other kingdoms and will devour the whole earth and tread it down and crush it.
In the Revelation to John, this final beast is described as a composite of the beasts described in Daniel 7. Most would say this is because this final kingdom encompasses the same geographical area as the Babylonian, Medo-Persian, and Greek empires before it. That is quite possible. But I would say that it is also possible that this final kingdom is described as a composite because it devours, treads, crushes and assumes control over contemporary kingdoms that come against it.
Then I saw a beast coming up out of the sea... And the beast which I saw was like a leopard, and his feet were like those of a bear, and his mouth like the mouth of a lion.