God is spirit. Heaven is spirit.
We don't have any words or concepts to accurately describe what that means.
Heaven is a timeless place where all of eternity is spread out and can be perceived all at once, by God.
We really don't have any good way to understand that or express it in language.
Some use phrases like "another dimension" etc.
Maybe that's why in the Bible four spatial dimensions are stated:
length, bread, width, and height.
Eph 3:17 so that Christ may dwell in your hearts through faith—that you, being rooted and grounded in love, may have strength to comprehend with all the saints what is the breadth and length and height and depth, and to know the love of Christ that surpasses knowledge, that you may be filled with all the fullness of God.
Those who are carnally minded will not understand. To understand spiritual things, we need to become spiritually minded. The Bible explains how that can happen. That's all I'll say on it.