Movie I can remmber the title or actors I only remember the story

The movie you described is probably based on the Henry James novel The Turn of the Screw. Identifying which movie or TV version you watched will be tricky because that story has been filmed about twenty times. It is one of the most highly regarded ghost stories ever written. Probably the most famous and acclaimed film version was released in 1961. That could be the film you saw. It was filmed in black and white. The title was The Innocents. Deborah Kerr played the governess.

Does this plot sound familiar? A rich man hires a governess, Miss Giddens, to look after his orphaned niece and nephew, Flora and Miles, at his large country estate. He makes it very clear that the governess is to handle all matters regarding the children. He wants to live at his home in the city and not be bothered with matters regarding their care.

Shortly after she is hired, Miles is expelled from his boarding school for an act so wicked that the school won’t reveal it. Miss Giddens is intially enchanted by the children. But over time she begins to worry about the behavior of the children. They seem to have a secret they are keeping from her. She learns from the estate’s housekeeper that the former governess, Miss Jessel, had a wicked affair with the groundskeeper, and that both died under mysterious circumstances. Miss Giddens becomes convinced that the children are being haunted by the spirits of Miss Jessel and the groundskeeper, and that they seek to corrupt the souls of the children.

At the end of the movie, Miss Giddens sends Flora away with the housekeeper so she can be alone with Miles. She wants to force the boy to admit that he is in contact with the evil spirits believing this confession will purify his soul and drive the spirits away. She demands over and over that the boy admit that he can see the ghosts. The boy denies it again and again, but she keeps shaking the child and screaming at him to admit that he is lying. Miss Giddens works the boy into a fit of hysterics and he dies in her arms. It is left to the audience to decide if the children were truly haunted, or if the ghosts were only in the imagination of the puranical, repressed Miss Giddens.

Even if you don’t think The Innocents is the exact film you watched twenty years ago (perhaps the film you watched was in color), you may still want to go to www.imdb.com and enter “Henry James” in the search field. You can see a long list of movies that were made from his stories. That list will include about twenty films based on his novel The Turn of the Screw. Eliminate those that were made in the last twenty years. One of the older versions may be the one you are looking for. But I bet the film you are looking for is this one:

https://www.imdb.com/title/tt0055018/?ref_=fn_al_tt_1