It depends on where in the ML spectrum you are. In RL it’s common to set agents to set some fraction of their time exploring and some other exploiting the environment. In neural nets there is the whole “online learning” field that addresses just that. It is generally possible but not always practical. There are other ways to update information. You mention ChatGPT. One way is giving them access to browsing to provide updated results. Technically one could retrain it on the conversations. I believe they will do it. But practically it makes more sense making it in batches e. g. Once a week or when a lot of new data has been accumulated. But yeah if you Google (or Bing lol) Online learning you will find a lot of papers