How to start a new browser tab

I have a go program that loads an HTML page to a browser, waits for form input, then sends another page depending on the input. I want to send the new page to a new tab instead of overwriting the initial tab. How do I do that?

I don’t understand your intentions yet, but it’s easier if you use it in an opera browser to drag and drop tabs via mouse clicks. Also using html code plugin in chrome is also a solution

I am not sure I have correct solution, but I would send open instruction to main tab and there using JS open new tab.