Confession of Sins

1 John 1:9 - If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness.

This is a hard topic sometimes. It is really important to always read the Bible in context. If you read from the beginning of the chapter, you will see that John is writing partially to unbelievers. He says, "We proclaim to you what we have seen and heard, so that you also may have fellowship with us. And our fellowship is with the Father and with his Son, Jesus Christ. We write to this to make our joy complete." 1 John 1:3-4

From their he basically gives a gospel presentation - We are all sinners. If we confess with our mouths and believe with our hearts we will be saved.
It is important to know the preceding verses to 1 John 1:9.

In 1 John 1:7 he says, "...the blood of Jesus, his Son purifies us from all (or every) sin."

In Hebrews 9:25-26 it says, "Nor did he enter to offer himself again and again, the way the high priest enters the Most Holy Place every year with blood that is not his own. Then Christ would have had to suffer many times since the creation of the world. But now he has appeared once for all at the end of the ages to do away with sin by the sacrifice of himself."

The key there is "once for all". If he has to forgive you every time you sin, he would have to make a new sacrifice every time.
If I have to confess every time I sin then it is no longer a free gift. I have to do something to earn it.

In Hebrews 10:10 it says, "By the will of God, we have been made holy through the sacrifice of the body of Jesus Christ once for all."

Again, it says, "Once for All". "We have been made holy". That means you are holy all the time. It is your nature to be holy.

This is why we say, "It is a finished work." Because Jesus finished all the work.
If you continually confess your sins, you will just remind yourself of how sinful you are and you will stay trapped in your sins. You will think that you cannot come before God.
But when you confess that God HAS made you righteous and holy, you will "boldly enter His throne room of Grace" (Hebrews 4:14-16). There you will find the grace to always overcome every obstacle.