Here’s a nice explanation of things:
an excerpt from the site:
“The Holy Spirit is God’s breath in us. God’s breath gives our bodies a special (divine) life, energy and enthusiasm. The Spirit makes us not only like the members of a team, but also makes us much more. We become the members of one body, Christ’s body. The Holy Spirit unites us in the Body of Christ so that, with him, we can call God our Father, actually “Abba,” which is more like daddy. It is this Holy Spirit that gives us our identity, that tells us who we are: the Body of Christ.”
I also recommend Leo J Trese’s book, The Faith Explained
Baptism, Eucharist and Confirmation are all sacraments of initiation.
“We are born in order to grow, and in growth our birth is perfected.” This fact can help us understand the relationship between baptism and confirmation. They are distinct sacraments in their own right, but the purpose of the sacrament of Confirmation is “to perfect in us that which was begun in Baptism” (The Faith Explained, Leo J Trese, p.335)
“The CCC says that Confirmation is the sacrament which gives the Holy Spirit in order to root us more deeply in the divine filiation, incorporate us more firmly into Christ, strenghten our bond with the Church, associates us more closely with her mission, and help us bear witness to the Christian faith in words accompanied by deeds.” (p. 337)
Acts 1:8 “You shall receive power when the Holy Spirit comes upon you,and you shall be witness for me…even to the very ends of the earth”
Confirmation strengthes and deepens our faith for our own needs and for the needs of others with whom we try to share our faith. Confirmation makes the path to Heaven easier and hopefully strengthens one’s faith so that it becomes less easy to lose one’s faith.