Jesus died at the cross and resurrected. He conquered the forces of the enemy and thus was victorious. He secured this victory for all those who will believe in His name and receive Him as Lord and savior - 1 Jn 5:4-5, Rom 8:37, 1 Jn 4:4.
Jesus was speaking to His disciples in Jn 16:33. He was reassuring them. He said to them that although there would be trials, tribulations, persecutions, challenges, etc. they did not need to be worried or concerned. Rather they should be at peace; confident in the victory that Jesus would obtain at the cross.
Jesus was not just referring to His disciples but to you and I, who are in a right relationship with Him. So the victory that you desire over the circumstances or challenges that you face has already been secured by Christ for you. Your ability to walk in this victory will be determined by how much revelation of this victory you have.
As you face challenges in this new year, be rest assured that you have already overcome. Your faith in God's Word concerning your victory is born out of revelation of God's Word. Seek out what God's Word says about your victory by searching though scriptures.
As you meditate on those scriptures you will come to a point that you receive revelation. Meditate on those scriptures until you have an image of victory in those challenging situations. Then celebrate victory irrespective of the natural circumstances - 2 Cor 4:16-17.
You celebrate because you have received your victory in the spiritual realm, where everything is created. Once you receive it in the spiritual realm, it will eventually manifest in the natural - Heb 11:1. So be of good cheer, Jesus has secured your victory - Jn 16:33.