Praise be to Allah.
Paradise has degrees or levels (we ask Allah to make us among its people), and Hell also has degrees or levels (we seek refuge with Allah from it). The people of Paradise will vary in their degrees or levels, according to the level of their faith and righteous deeds in this world. The best of them in knowledge, righteous deeds and faith will be the highest of them in the levels of Paradise.
The people in the lowest levels will not be able to attain what is in the highest levels, because they did not do that which makes them deserving of attaining those levels.
If all the people of Paradise were to share in the bliss that Allah has prepared for those who are above them, then there would be no wisdom in the variation of status and degree!
By Allah’s perfect justice, those who are deserving of Paradise will not all be the same in degree or level of bliss. Variation between people in this world in terms of faith and obedience leads to variation in their status and standing before Him, may He be glorified and exalted.
See the answer to question no. 126349.
The people of Paradise will be in a state of eternal bliss, whether they are of the highest levels or less than that. There they will have whatever they wish for, as Allah, may He be exalted, says (interpretation of the meaning):
“Gardens of perpetual residence, which they will enter, beneath which rivers flow. They will have therein whatever they wish. Thus does Allah reward the righteous”
“For them therein is whatever they wish, [while] abiding eternally. It is ever upon your Lord a promise [worthy to be] requested”
“Circulated among them will be plates and vessels of gold. And therein is whatever the souls desire and [what] delights the eyes, and you will abide therein eternally”
Ibn Katheer (may Allah have mercy on him) said:
“They will have therein whatever they wish” i.e., of pleasures, such as food, drink, clothing, dwellings, means of transportation, views and so on, such as no eye has seen, no ear has heard, nor has it ever crossed the mind of anyone.
End quote from Tafseer Ibn Katheer (may Allah have mercy on him)
Al-Sa‘di (may Allah have mercy on him) said: i.e., no matter what they wish for and long for, they will get it in the fullest and most perfect manner. They will never able to ask for any kind of delight that would bring them pleasure and great joy, but it will be granted to them. Hence Allah will give the people of Paradise what they wish for, to the extent that He will even prompt them to ask for some types of delight that never even occurred to them.
End quote from Tafseer as-Sa‘di (p. 439; see also p. 579).