will there be levels in jannah?
Yes, According to some verses like the one quoted below, Paradise does have different levels:
لَّا يَسْتَوِي الْقَاعِدُونَ مِنَ الْمُؤْمِنِينَ غَيْرُ أُولِي
الضَّرَرِ وَالْمُجَاهِدُونَ فِي سَبِيلِ اللَّـهِ بِأَمْوَالِهِمْ
وَأَنفُسِهِمْ ۚ فَضَّلَ اللَّـهُ الْمُجَاهِدِينَ بِأَمْوَالِهِمْ
وَأَنفُسِهِمْ عَلَى الْقَاعِدِينَ دَرَجَةً ۚ وَكُلًّا وَعَدَ اللَّـهُ
الْحُسْنَىٰ ۚ وَفَضَّلَ اللَّـهُ الْمُجَاهِدِينَ عَلَى الْقَاعِدِينَ
Not equal are those believers remaining [at home] - other than the
disabled - and the mujahideen, [who strive and fight] in the cause of
Allah with their wealth and their lives. Allah has preferred the
mujahideen through their wealth and their lives over those who remain
[behind], by degrees. And to both Allah has promised the best
[reward]. But Allah has preferred the mujahideen over those who remain
[behind] with a great reward - http://tanzil.net/#4:95
وَمَا أَمْوَالُكُمْ وَلَا أَوْلَادُكُم بِالَّتِي تُقَرِّبُكُمْ
عِندَنَا زُلْفَىٰ إِلَّا مَنْ آمَنَ وَعَمِلَ صَالِحًا فَأُولَـٰئِكَ
لَهُمْ جَزَاءُ الضِّعْفِ بِمَا عَمِلُوا وَهُمْ فِي الْغُرُفَاتِ
And it is not your wealth or your children that bring you nearer to
Us in position, but it is [by being] one who has believed and done
righteousness. For them there will be the double reward for what they
did, and they will be in the upper chambers [of Paradise], safe [and
I heard all wishes would be accepted in jannah so i wish myself to be upper level of jannah will i be granted that.
In paradise people are completely unaware of existence of a higher level and anything about upper levels is removed from their minds. Since this is the key of harm when you see people having some things better than you don't have. The wishes are limited to those things which will be available in that particular level one is in. In fact you will never wish of anything unseen or have any unawareness of them. For example, a baby never wishes to have sex because it has no awareness of such a phenomenon. Or a man who is living alone in an island and has never seen or heard anything about grapes will never have wish for them.
And could you tell more about jannah levels.
Usually it is said levels of paradise are equal to the number of verses in Quran and by knowing and practicing a verse in life one goes to higher level. In fact who knows, obeys and practices all verses of the Quran during his life will reach the highest level of paradise. Only reading or memorizing Quran is not enough, although memorizing them has its benefits.
Let's say I wasn't that good and went to lower level but after living long time there will i be able to move to another level, as people would come out of hell after their punishment is over. Not getting full benefits or enjoyment is also sort of punishment in a way.
Yes but this is if the person is aware of the existence of a higher level. Your mind is under the control of God and God can clear anything from the mind of people and does it in this world as well when God wants to interfere in regular happenings of the world and assist his messengers and friends.
فَلَا تَعْلَمُ نَفْسٌ مَّا أُخْفِيَ لَهُم مِّن قُرَّةِ أَعْيُنٍ
جَزَاءً بِمَا كَانُوا يَعْمَلُونَ
No person knows what is kept hidden for them of joy as a reward for
what they used to do. http://tanzil.net/#32:17