Male infertility

My fellas sperm has all died and so now I have no idea of all the other options what we can do. Any ideas? I’ve been really depressed over the last few days as only found out on Friday. He still need to do more tests so hopefully will find out what has caused it all. He does smoke a lot. But we are trying to quite completely but this has just upset us so we have started smoking again. I’m just so lost