It's a fistula from the infection.
The tooth is not restorable based on your endodontist, then the normal procedure would be:
Antibiotics for 7 days;
Reevaluate the infection to makesure it's clear;
Extraction and implant placement, with or without bone graft;
Abutment and Crown when the implant is ready.
The alternatives would be a bridge, a partial denture, or nothing.
Good luck.