Bad breath

My boyfriend has bad breath due to bad teeth.

He does brush and I've asked him to start flossing and using mouth wash. He says he is.

The issue is he didnt brush his teeth for a long time period due to being homeless so now his teeth hurt and gums bleed everytime he brushes.

I am going to buy him toothpaste for bleeding gums(I use colgate sensitive so thats what hes using right now).

He is aware of his breath,I ask him to go brush his teeth when I notice it. Im also constantly asking if im nagging or being rude when telling him that. He says it doesnt bother him.

Anyways my question is...

Whats the best mouth wash to use?

As soon as he gets a job and dental he is going to the dentist but for now .. help lol

Edit:his breath smells fine after he brushes, i just have to be sure he actually brushes more then once a day but it doesnt last all day or longer then an hour.

Ive never delt with an issue like this I have good hygiene and im now teaching him how to have good hygiene.

And i am aware he needs to see a dentist, he is looking for work so he can go.

There arent any dentist schools around here,my friends dentist office she works at does do feel dental care once a year but they had it last week and she didnt announce it on her Facebook this time so we missed it