If your boyfriend believes in fortune telling, then you need to consider his beliefs and values. Perhaps his family and cultural background think that fortune-telling is an important traditional culture, or maybe he is influenced by some events, which makes him feel uneasy about his fate and future. No matter what his reasons are, as his partner, you should respect his beliefs and feelings and try to understand his thoughts and feelings.
Of course, if his fortune-telling belief affects your relationship, you can also try to communicate with him in depth. You can tell him that fortune telling can't really determine a person's future, but our own choices and efforts determine our destiny. You can make plans and goals with him and work hard to achieve them.
Most importantly, no matter how you treat his fortune-telling belief, trust and communication between you are very important. Only through frankness and understanding can you build a healthy and stable relationship and face the challenges in life together.