How do you get peace? The Bible says in Isaiah 26:3, You will keep him in perfect peace, Whose mind is stayed on You, Because he trusts in You.
You simply have to get your mind off the problems and make your mind STAY on God. It will take some work, but after a few days it will be easy. Every time a thought comes that doesn’t line up with what the Bible says about your situation – stop! Stop your thoughts! Speak out loud what the Bible says about it! And command peace to come back to you. Think about a puppy when you are teaching him to stay. It’s the same process – it takes time – but your mind will learn to stay on God and when your mind stays on God, peace will stay also.