Is there a Bible verse that discusses the importance of being filled with the Holy Spirit?

Yes, many. The Holy Spirit is the Spirit of Christ. Without His Spirit you’re not born again. Unless you are born again you won’t see His Kingdom. (John 3)

Romans‬ 8‬:7‬-11‬ “For the sinful nature is always hostile to God. It never did obey God’s laws, and it never will. That’s why those who are still under the control of their sinful nature can never please God. But you are NOT controlled by your sinful nature. You are controlled by the Spirit IF you have the Spirit of God living in you. (And remember that those who do not have the Spirit of Christ living in them do not belong to him at all.)
And Christ lives within you, so even though your body will die because of sin, the Spirit gives you life because you have been made right with God. The Spirit of God, who raised Jesus from the dead, lives in you. And just as God raised Christ Jesus from the dead, he will give life to your mortal bodies by this same Spirit living within you.”

Acts of the Apostles‬ 2‬:36‬-40‬ “So let everyone in Israel know for certain that God has made this Jesus, whom you crucified, to be both Lord and Messiah!” Peter’s words pierced their hearts, and they said to him and to the other apostles, “Brothers, what should we do?”
Peter replied, “Each of you MUST REPENT of your sins and turn to God, and be baptized in the name of Jesus Christ for the forgiveness of your sins. THEN you will receive the gift of the Holy Spirit. This promise is to you, to your children, and to those far away—all who have been called by the Lord our God.” Then Peter continued preaching for a long time, strongly urging all his listeners, “Save yourselves from this crooked generation!”