I have a Garmin Forerunner 255 and I would like to add certain activities to the watch, if possible, such as elliptical and rowing machine.
Click the upper right button once. Then click the lower left button repeatedly until you see the screen that says "Add." Click the upper right button again. Then click the lower left button until you get to "Gym" and hit the upper right button to select it. "Row Indoor" and "Elliptical" are both options to add to your watch.