Holy Spirit connects God and us and exists with God at the beginning. Genesis 1:1 says, “..the Spirit of God was hovering over the waters.”
The Spirit of God is ubiquitous, so we can ask God to fill Holy Spirit up. Bible says, “Do not get drunk on wine, which leads to debauchery. Instead, be filled with the Spirit” (Ephesians 5:18).
The characteristic of the Spirit of God is described in Bible despite the fact no one can see its substance. Bible says, “These are the things God has revealed to us through the Spirit. For the Spirit searches everything, even the depths of God. For who knows a person’s thoughts except the spirit of that person, which is in him? So also no one comprehends the thoughts of God except the Spirit of God” (1 Corinthians 2:10-11).