I have heard a lot of people talk about what brings them anxiety. Paul is commanding us here to be anxious for nothing or better yet don’t be troubled with cares. You’d be wrong to think God is not concerned about what makes you anxious. Paul tells us to give it to God. Open the line of communication with God by prayer and with supplication, ask God to do something.
Jesus commands us in Matthew 6:25 not to worry about life. The word worry here is a different word than the one in Philippians, but also means to be anxious. Being anxious removes us from being a child of the house to being the father of the house. A position that, as children of God, belongs to God.
So make your request known to God. Tell Him everything, big or small. Because the verse that follows says “and the peace of God, which surpasses all understanding will guard your hearts…” (Philippians 4:7).