Currently, it is not possible to block ChatGPT from crawling or using your site content because ChatGPT does not directly crawl websites for data. It uses past data collected by third-party and open-source website crawlers for training.
Some of the known data sources used to train ChapGBT include Wikipedia, Free Books, WebText2, Reddit Content, Common Crawl, etc.
If in the future ChatGPT will start crawling websites for real-time data for example news information, then we will probably know the specific ChatGPT crawler or bot name.