The habit that has brought me the most joy, is to take a moment for gratitude every day. It has changed my entire life for the better.
Nothing really matters because, in the end, we are all just beings, existing in this universe. We don't have an ultimate higher purpose, at least unless you decide to have one. You can go an entire lifetime without a purpose, and you would still exist and be as you are.
If you want to learn how to stop feeling anxious thoughts and worrying, this method teaches you how to use positive affirmations for anxiety.