ChatGPT Browse with Bing is a feature (available to paid users) that allows ChatGPT to search the internet to help answer questions that benefit from recent information.
Browsing is integrated into a single unified model, accessible when you select GPT-4 from the model selector. If you ask a question in the chat that requires the use of the Browse feature (ex. What is the weather today in NYC?), the model will automatically enable the Browse feature to provide you with an answer.