Hi CJSophie
What you are trying to do requires you to reinforce two behaviors.
1) You can reward your dog for ringing the bell by letting him out. Over time, you will indeed be training your dog to ring a bell whenever he wants to go outside. I don't think you can really train your dog to ONLY ring that bell when he really needs to go.
2) You must reward your dog after he's done his business with a treat and praise. This means that yes, you have to outside with him even if it's winter (I did this with my puppies). You can even say a command while he is doing his business (I use the command "duties"), and after 3 weeks you'll be able to say "duties!" and your dog will go on command.
What you are trying to do requires you to reinforce two behaviors.
1) You can reward your dog for ringing the bell by letting him out. Over time, you will indeed be training your dog to ring a bell whenever he wants to go outside. I don't think you can really train your dog to ONLY ring that bell when he really needs to go.
2) You must reward your dog after he's done his business with a treat and praise. This means that yes, you have to outside with him even if it's winter (I did this with my puppies). You can even say a command while he is doing his business (I use the command "duties"), and after 3 weeks you'll be able to say "duties!" and your dog will go on command.