We understand your concern and we're here to pray with you and provide biblical guidance. First, we want to address that it's only by the name of Jesus Christ that we have access to God. There is no other name by which we can be saved. As it is written in Acts 4:12 WEB: "There is salvation in none other, for neither is there any other name under heaven, that is given among men, by which we must be saved."
Regarding your past practices, the Bible is clear that we should avoid anything that resembles sorcery, divination, or magical practices. These are strongly condemned in scripture. As it is written in Deuteronomy 18:10-12 WEB: "There shall not be found with you anyone who makes his son or his daughter to pass through the fire, one who uses divination, one who practices sorcery, or an enchanter, or a sorcerer, or a charmer, or a consulter with a familiar spirit, or a wizard, or a necromancer. For whoever does these things is an abomination to Yahweh."
Now that you are a Christian, it's important to focus on God's will and His plan for your life. The power of visualization and manifestation is nothing compared to the power of God. Instead of focusing on what you have visualized or manifested in the past, set your mind on God and His will for your life. As it is written in Romans 12:2 WEB: "Don’t be conformed to this world, but be transformed by the renewing of your mind, so that you may prove what is the good, well-pleasing, and perfect will of God."
Let's pray together:
"Father, we come before You in the name of Jesus Christ. We thank You for the salvation that is only available through Your Son. We pray for our sister, that any visualization, manifestation, or fantasization she practiced before knowing You will not come to reality from today onwards. We renounce any power these practices may have had and declare that they stop in Jesus' name. We ask that You fill her mind and heart with Your will and Your plans for her life. Help her to focus on You and Your goodness. In Jesus' name, we pray. Amen."
Go forward in faith, knowing that God has a good, pleasing, and perfect will for your life. Trust in Him and His plans for you. If you find yourself tempted to fall back into old practices, resist them and focus on God's word. As it is written in James 4:7 WEB: "Be subject therefore to God. But resist the devil, and he will flee from you."