You can start with Tchaikovsky's music. His music has a strong sense of melody, and with a little explanation (you can find music appreciation books or search directly on the Internet), so it is not difficult to understand the overture of 1812 and the scene of Swan Lake, and then listen to other composers' songs, focusing on melody rhythm, ups and downs, etc. In fact, there is no fixed standard for people to understand and listen to classical music. As long as they feel good and comfortable, it will be fine.