Hello. Firstly, the most important thing to keep in mind Post Root canal treatment is that the tooth becomes brittle. Please make sure that you need to get a permanent filling rather than a temporary one and above that a full coverage restoration ( crown) . The reason for bleeding on brushing and bad breathe could be that you have deposits in your oral cavity and you have avoided professional teeth cleaning ( scaling) in the last 6 months. Please visit a dentist for a detailed consultation post which a through professional cleaning and post X Ray for your Root canal treated teeth( if the root canal is completely fine with no signs of infection) then go ahead with full Coverage restorations ( crown )

You have to undergo the complete treatment of root canal treatment and permanent filling and followed by a crown which would be if ceramic or zirconia then only the problem would resolve

We could help you with both. Root canal treatment could be completed and the smell may be due to pus accumulation which will be cleared. A mouthwash for better breath and root canal will take care of bleeding