We know Jesus sits at the right hand of God, Mark 16:19, (some verses say stands at the right hand) and the reason for this is that Jesus is our mediator, John 14:6, between man and God as man cannot look upon the face of God and live, Exodus 33:20, as God can not look upon the flesh of man for it is sinful, Habakkuk 1:13, and Gods countance is to brilliant for man to look upon. It would be like trying to look at the sun as it is too bright for us to look at with our own eyes. In Exodus 33:20, 23 God told Moses that he could see Gods back parts only as God placed Moses in the crevices to shield him as he passed by him as no one could see his face and live. Gods back parts that we still see today as Moses saw then is Gods grace and mercy on his people that even though we might not be able to see God we always know that he is always with us as his word says he will never leave us or forsake us, Hebrews 13:5.
The only ones who will ever see the throne of God are those of a heavenly spiritual creation in the third heaven, (Bible speaks of three heavens as explained below) which are the angels, Jesus, as now he is in his glorified state, Matthew 17:2, that shines like the sun without flesh and bone, but will return visible for all to see him, Acts 1:9-11, in the same way he ascended visibly and was consumed by the clouds and could no longer be seen by anyone as this is when Jesus was changed from flesh and blood to his immortal state of being spirit once again, 1Corinthians 15:50. Satan, who is also spirit form, can be found at times standing before the throne of God accusing the brethren, but even though he is still in heaven he only has limited access to the throne room of God as he goes to and fro between heaven and earth for now, Job 1:6; Revelation 12:7-12.
No one has or ever will enter into the third heaven where God sits on his throne as it is not a literal place we can see with our own eyes, but that of a Spiritual realm reserve only for that which is created Spiritual. According to John 14:2 Jesus is preparing a new heaven (Atmosphere) and a new earth that he will usher down after the tribulation of those days before his return, Matthew 24:29-31, as when Jesus comes back in the clouds as they have seen him leave he will raise up his Bride into the clouds to meet him in the air, 1Thessalonians 4:14-18, and than will he come down to plant his feet on the Mount of Olives to make an end of the abomination of sin once and for all and ushers down from the third heaven the new Jerusalem and new earth, Zechariah 14:4; Revelation 21:1,2. Those that are in Christ that have died to the grave and those alive will the angels gather from the four winds of the heavens, Matthew 24:31, and then will be changed in a twinkling of an eye as mortality will put on immortality, corruption will put on incorruption, 1Corinthians 15:51-55 and we will reign with Christ in our new bodies in the reward of the inheritance of the new heaven (Atmosphere), new Jerusalem and new Earth as we will reign with Christ for eternity, Isaiah 65:17-25; 1Corinthians Chapter 15.