How do you find out your COBRA premium amount

Husband recently lost his health coverage due to losing his job.  He is in need of going to the doctor as he has a possible blood clot and Factor 5 disorder.  His employer hasn't sent any COBRA information so not sure where to go from here.  We can still log in and see his claims but can't find anyway to continue his coverage.  

Thank you so much in advance four your help!

Cara