Enhance my new GPT recommending marketing strategies

Hey folks,

I’m seeking the way to tell my new GPT to browse specific and dedicated websites prior in order to be more skilful before it serves as an agent. I want it to be proficient as a marketing specialist, and there are great websites where you can get knowledge and inspiration. Where in the custom GPT configuration panel, you can set up this rule to browse a specific list of websites.

Best regards,