How do I get the actual train number for the reservation I have?

1 to Los Angeles CA, 2 From LA, 59 From Chicago, 19 From New York/DC

It should be located on your ticket or reservation. Going to New York is train 20, going to Chicago is train 58, and going to Los Angles is train 2

There are only 6 numbers for trains, city of new orleans is train 58 north bound 59 south bound. Amtrak website can tell you the numbers for crescent or sunset limited. Or if you booked you should get a confirming email with the numbers

Have you tried online or calling