We are glad that you have come seeking forgiveness and help. Looking at inappropriate material is sinful and is considered lust and possibly pornography. The Bible tells us to flee from sexual immorality and honor God with our body. (WEB 1 Corinthians 6:18-20 "Flee sexual immorality. Every sin that a man does is outside the body, but he who commits sexual immorality sins against his own body. Or don't you know that your body is a temple of the Holy Spirit who is in you, whom you have from God? You are not your own, for you were bought with a price. Therefore, glorify God in your body and in your spirit, which are God's.")
In order to be forgiven, we must confess our sins to God through Jesus Christ. The Bible says "If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness." (WEB 1 John 1:9). If someone claims to repent and yet knowingly continues in their sin they are taking the Lord's forgiveness lightly, such as in (WEB Proverbs 28:13 "He who conceals his sins doesn't prosper, but whoever confesses and renounces them finds mercy."). We are to find mercy through confessing and renouncing or forsaking sin. We are not only to confess but to also turn away from our sinful behavior.
Notice, in order to be forgiven by God you mentioned nothing about Jesus Christ, Jesus, Christ, or an abbreviation such as IJN (In Jesus Name). It is only by the name of Jesus that we have access to God. Also, there is no other name by which we can be saved (WEB Acts 4:12 "There is salvation in no one else, for there is no other name under heaven given among men by which we must be saved!").
So let us pray. Heavenly Father, we come before you in the name of Jesus confessing this sin and renouncing the lust that was allowed to cause this fall. Thank you for forgiving us. In Jesus name, we ask that you will help to deliver from this temptation and give us the strength to resist. In Jesus' name, we pray for a pure heart that is sensitive to the conviction of the Holy Spirit when tempted. In the name of Jesus, break any addiction to this sin and any strongholds of the devil that this has allowed. We ask this all in Jesus Christ's name.
Therefore, put your sins behind you and do not focus on the failures of the past. Instead press on toward the goal to win the prize for which God has called you heavenward in Christ Jesus (WEB Philippians 3:13-14).
We pray that you will know the saving power of Jesus. "that if you will confess with your mouth that Jesus is Lord, and believe in your heart that God raised him from the dead, you will be saved. For with the heart, one believes unto righteousness; and with the mouth confession is made unto salvation." (WEB Romans 10:9-10).