What is the closest train that goes to this museum

The B and C trains let you off right in front of the Museum - exit at 81st Street (keep in mind that the B only runs on weekdays, but the C runs seven days per week). You can also take the 1 train to 79th Street. https://www.amnh.org/plan-your-visit

I do not know, sorry. Look at a subway map. Good luck.

Stop 81 on B or C lines is right in front of the museum.