Help me find a Japanese love anime movie.

If I remember correctly, LZ should be talking about the first TV movie "Listen to the Sound of the Waves" in Studio Ghibli, Miyazaki Hayao.

The hero and heroine of the story are Du Qi and Wu Teng. Wu Teng somehow transferred from Tokyo to Du Qi's school. Wu Teng wanted to raise money to visit his father in Tokyo, so he lied that he had lost his money and borrowed it from Du Qi, forcing Du Qi to accompany Wu Teng to Tokyo in the future. Two people in Tokyo hotel muddleheaded cohabitation for a night, Du Qi consciously sleep in the bathtub. ..... At the class reunion one year later, Du Qi learned that Wu Teng had been admitted to the University of Tokyo secretly, regardless of his mother's objection. Someone asked her why, and she said that he wanted to meet someone in Tokyo. When asked who she was, she said someone was sleeping in the bathtub. Du Qi realized that Wu Teng had always loved him, but he was unaware of it.

At the end, Du Qifeng finally reunited with Wu Teng on the platform, and the waves in his heart rose again. At this time, there is no dialogue between them, only their eyes are intertwined. Let's fill their future years with our best imagination. ...

The theme song sung by Wu Tengsheng is ED-"Hai になれたら", which is really nice and I like it very much.