Hi Denise,
Heaven is difficult to understand, because it is a spiritual place and all we have to relate to is physical things in this world.
Your question;
I'm trying to understand this. if Jesus is in heaven, which heaven means it is within us. How will Jesus make his return?
The heavenly kingdom is not of this world it is another world or realm altogether.
That's why Jesus said not to bother looking for it, it's not a location.
John 13:1 And before the feast of the Passover, when Jesus knew that His hour had come when
He should depart out of this world to the Father, having loved His own in the world, He loved them to the end.
John 18:36 Jesus answered,
My kingdom is not of this world. If My kingdom were of this world, then My servants would fight so that I might not be delivered to the Jews.
But now My kingdom is not from here.
The kingdom of heaven is a spiritual realm, and those who have the Holy Spirit given to them, this spiritual understanding of truth comes into them.
John 15:26 Now, whenever the consoler which I shall be sending you from the Father may be coming,
the spirit of truth which is going out from the Father, that will be testifying concerning Me."
1Th 4:8 Therefore he who despises does not despise man, but God, who also
has given us His Holy Spirit.
This is the few, the elect that now have a taste of the kingdom of heaven, now in this life. But they will not enter into the spiritual heavenly realm until they have been faithful to the end, and when Jesus appears, they will be like Him, SPIRIT.
John 3:6 That which is born of the flesh is flesh, and that which is born of the Spirit is spirit.
v. 7 Do not marvel that I said to you, 'You must be born again.'
v. 8 The wind blows where it wishes, and you hear its sound, but you do not know where it comes from or where it goes. So it is with everyone who is born of the Spirit."
Hope this helps
mercy, peace, and love
Kat