Not getting 2.5A or 2 A DC current
OK, you're working on a breadboard.

Breadboards have so much contact resistance that it will be impossible to make your circuit work properly. You expect a couple of Ampere to flow, that's not going to happen in this setup.

I would only rely on a breadboard for currents up to 100mA, for higher currents the voltage drop across wires and contacts is simply too high preventing the circuit from behaving as it is designed to.

Also you're not using any heatsink on the voltage regulator so even if a high current would flow it would heat up and limit the current to protect itself.

Your circuit's schematic looks OK, you just need to build it on some prototype PCB (or veroboard) so that you have soldered contacts instead of plug-in contacts as on a solderless breadbord.