Why my laptop doesn't work

@adamagha commonly this would be a motherboard error. Let's see if we can narrow it down.

First do this. Disconnect the power from the computer by unplugging the power cord from your computer. Disconnect all external devices from the computer. Remove the bottom cover screws and carefully lift off the base panel. Disconnect the internal battery cable from the motherboard connector. Now hold the power button depressed for about 1min.

Leave the main battery disconnected for now. Plug the AC adapter back into your laptop. Now watch the Caps Lock light. If the light stays OFF you'll now that the power management was successfully reset. If so, you can now plug the battery back in

If the above has not made a difference, we must consider that on many Dell architectures, a completely dead CMOS battery can cause the laptop to automatically turn on and throw an immediate loop error (indicated by the continues blinking) as soon as the laptop is plugged into a wall outlet. Unplug that battery from your motherboard and wait 5 minutes. Now, plug your AC adapter back into the laptop without the CMOS battery connected. If the continuous flashing stops and the laptop attempts a normal sequence, replacing the CMOS battery should fix your issue.

Anything past these previous attempts will require testing and checking of the motherboard. For that, we would need to see the motherboard (both sides) as well as know the motherboard number. It will be printed on the motherboard itself. Adding images to an existing question