How can i access my broken phone to verify my facebook account

You can access some data on iCloud.com provided that you can still sign in your Apple ID there. If in case you are needing the codes sent to the phone number and you can't get them because the phone is not working, you can try taking out the SIM card and put it inside a working phone so you can get the codes if they are sent via SMS

Hope this help! Best of luck!

When you get it Repaired by an Apple Repair and Repair Status Check - Official Apple Support or purchase a new iPhone

Restore your iPhone, iPad, or iPod touch from a backup