I'm new to Davinci Resolve, and when I try to make difgferent clips out of the main video I don't know how to export that clip segment instead of erasing all the video and loosing all the marks, as I would like to have different clips out of this big video.
As a new user, your first course of action should be to complete some Resolve training. The Beginner's Guide and Advanced Editing are an excellent groundwork to get you moving smoothly.