I know that I can change the color of an LED. I also would like to change the size that appears on the screen because it is so large that is covering the resistor right behind it. Can that be done? Thanks.
Only by using a different led part that is smaller. If you click on the led in breadboard, then look in Inspector, (bottom right of the screen) you can change the default 5mm LED to a 3mm led in the package field and the led will get smaller in breadboard (it is actually loading a different part). There are also alternate (not in core parts) leds, square that are designed to fit between .1 centers. Depends what you want / are willing to accept. I or one of the other part makers can also cut down the size of a standard led.