2001 astro hd lights on all the time. How can I turn them off?

Your hd lights automaticly turn on when you turn on the van right there running day lights set by the factory, on my van theres a button labeled ''dome overide'' ok with ur van running try pushing and holding down that button for few sconds doesnt always the first time, once there off if wish to turn them back simply turn the van off so they could reset themselves.

Is there a fuse for chevy 2001 astro van inside the engine compartment or is it in the driver side door jam area , for the fuel pump

If the headlight switch does not shut the lights off replace the switch.
unplugging the lights or disconnecting the battery is another option to turn off