The Bible doesn’t specifically address shyness, but God does say He wants us to interact with people through serving them, discipling them, and telling them the good news.
Some people develop shyness because they place too much importance on what other people think of them. They retreat and decide, actively or passively, to not interact with others for fear of rejection. This can be grounded in fear or pride. Both fear and pride are ungodly (Ephesians 6:6–7; Proverbs 29:25; 1 Peter 5:5) and should be replaced with faith in God (Hebrews 11:6; 1 John 4:18–19).
God’s view of us should be our primary concern, not another person’s opinion of us. The Bible tells us that Christians are not to live as those in the world live, and by living to please God, many people will not like us (2 Timothy 3:12). When shyness emanates from a concern over the opinions of others, we do well to remind ourselves who we are in Christ (see Ephesians 1). Focusing on His love for us can help us overcome any shyness that might be hindering us.
Another way to overcome shyness is to transform your mind (Romans 12:2) and ask God to help you focus on what He would have you do. When our minds are set on obeying God and serving others, instead of distracted by our own discomfort, it is easier to overcome shyness. Colossians 3:1–4 is a helpful Scripture to cling to. Second Timothy 1:7 is another: “God gave us a spirit not of fear but of power and love and self-control.” When we rely on the Holy Spirit, He will help us obey His call.
It should be noted that while Christians are called to make disciples (Matthew 28:19–20), fellowship with one another (Hebrews 10:24–25; Colossians 3:12–17), be prepared to share the gospel (1 Peter 3:15), and interact with people in a variety of other ways, none of this must occur in a large crowd or an overtly public manner. Not every Christian is called to be a public speaker, for example. But we are all called to obey God and to actively love others. Sometimes this requires stepping outside our comfort zone and interacting with people we would rather not.
Christians need not be bound by the fear so often associated with shyness. In Christ, we are free to be who He has made us to be and to do all that He has called us to do (Ephesians 2:10; Galatians 5:1). When shyness gets in the way, we need to remember that God is with us and rely on Him to give us the confidence to obey.
source: https://www.compellingtruth.org/Bible-shyness.html
