Does DCC require more than one power/Command Plus to terminal connection?

Can you use the red cords to attach power to and from terminal/rerailers for DCC? I have the Command Plus controller and still haven't figured out how many engines or turnouts I can run cause of power at one time. Probably stupid question but thanks. Probably got too much stuff for a beginner. 4 x 12-14 ft with two major outside loops.

Can someone please explain what the differences for radius or length for the switches / turnouts...... than this one has an extra piece or same as dc? If it is. Degrees, inches, radius? Thanks.