Welcome, Shandy.
Do you have a Bible? Many churches will give you a free one if you don't have one.
Becoming a Christian is not like joining a club. It is joining yourself to God your Creator. You do this by just talking to Him in prayer.
1. Start by asking Him to forgive you for all the bad choices you have made. The Bible calls all your imperfections sin. Since you are not perfect, ask Him to forgive you for being a sinner.
2. Thank Jesus for dying on the cross to pay the death penelty for your sinfulness. Ask Him to cleanse you of all your filth; then give Him your life to make you a whole new person. (He will change your desires so you will want to become more and more like Jesus.)
3. Ask the Spirit of Jesus, the Holy Spirit, to come into you to live in you. Ask Him to teach you from the Bible and help you to understand more about Who God is and what it means to be a Christian. Ask Him to guide you to a good church
There are a lot of differences in churches. Some are very formal, some very informal. But the best ones teach straight from the Bible every Sunday. They may teach on a whole chapter of the Bible and go through it explaining it or helping us see how it applies to our lives, today.
You need to find one that is loving, that welcomes and accepts you.
Usually you have to make an appointment to speak to the pastor, but often the pastor and assistant pastors are available after church to talk to. I would urge you to just walk into a church on a Sunday morning and visit it. They usually post a sign outside telling when their services are. Usually they are around 10 to 11 AM. But you may have to call the church office to find out.
Most churches have different ways of joining the church. Some invite you to take classes first and some urge you to do so afterwards. These classes aide in getting acquainted with the Bible and with Christianity. But it is easiest to understand everything if you have already asked the Spirit of Jesus to live in you. Most churches will ask you to stand up and confess your faith in Christ in one way or another as part of joining the church. It is not necessary to join a church to become a Christian. It is necessary to confess your faith in Christ to others. "that if you confess with your mouth the Lord Jesus, and believe in your heart that God raised Him from the dead, you will be saved." Romans 10:9 New King James Version. And I do urge you to attend a church regularly.
You are also free to post questions on this board. Just take from it what you need and is meaningful to you if it is posted by another Christian. We are still learning, too, and will be till we get to heaven. A few of us have some weird ideas, so pray about the answers and compare them to the Bible. This is true even if it is a pastor or minister who talks to you.