RE: how does it works to train the bot and how can i do this

The bot will find the best known response for a question. First it will check it's program scripts, then it will look for an exact match for the question, then it will look for a question similar to the question. If none of these find a good match, then it will use the default response.

You can create a new bot using the empty template to have a bot with no built-in phrases.

A phrase is a sentence.

The Chat Logs page is the best place to review and correct responses.