This document answers these questions and more. It is the explanation that accompanies the Small Catechism, the short teaching. It is authoritatively from the revealed mystery, a light in the darkness, God's Holy Writ.
Need some serious answers?
Believe in Jesus? Which? The law maker or the law full-filler? One's personal Jesus may not match Jesus of the Bible. Test, see if what you believe is what the God says. Do so in the company of peers, like steel sharpening steel. Baptism? Is it something you do for God or is it a gift He gives you? This gift is faith that receives favor won by Christ's cross. Be careful to believe rightly and pray the Lord removes misbelief.