How to drag a crosshair on macbook pro 2019 trackpad for a screenshot

The apple support instructions explain how to do a screen shot by using appropriate keys to get a crosshair. I then need to drag it to highlight the area of the page to screenshot. The instructions do not explain how to drag it. I do find the trackpad gestures on my new 2019 macbook a nightmare - so much more difficult to use and remember than on my old 2010 macbook air. I often have to go back to using my old macbook since the new one is so non-intuitive.