>>19164148Look up famous composers find out what their most famous works are, and listen to them. Look up famous composers, find lists of all their compositions (Like Bach-Werke-Verzeichnis, Ryom-Verzeichnis, or Opus number, etc, depending on the artist) and work through listening to it like it's a todo list. It also helps to review them and/or take notes after you are done listening to them so they are easier to remember (since a shit load of classical music pieces have generic sounding names).
Here is a small list of compositions that are famous off the top of my head.
Ludwig Van Beethoven - 5th symphony, 9th symphony.
JS Bach - Goldberg Variations, Well tempered Clavier, Toccata and Fugue in D minor, Mass in B minor.
Mozart - Requiem in D minor, Symphony No. 40 in G minor, Don Giovanni, Piano Concerto No. 24 in C minor.
Antonin Dvorak - New world Symphony
Pyotr Ilyich Tchaikovsky - Swan Lake, The nutcracker.
Antonio Vivaldi - Four seasons
Franz Schubert - Fantasia in F minor, Ave Maria, Trout Quintet
Other important composers that I know about but haven't listened to very much (off the top of my head) are
Richard Vagner, Joseph Haydn, Frederic Chopin, Felix Mendelssohn, George Frideric Handel, Franz List .
I haven't dedicated a shit load of time to reading about classical music history, or listening to classical music I probably forgot (or don't know) some important ones.