Hello
You have to unlock the device.
Check the appearance of the motherboard to see if there is any burn or water damage.
Then, check the power supply status of the motherboard with a multimeter if there is no connection.
Then measure the voltage and see if the voltage enters the motherboard?
What voltages are available and what voltages are not available.
First, you must have 19 volts on the input jack.
Then you should have 19V at B+ position.
The rest of the motherboard voltages are made from B+.
Some of them are in the form of regulators, such as 3.3 V LDO, which is produced at the beginning, and the main power supply is SIO, PCH, and Hall sensor.
In the next step, when the IO is turned on, standby voltages are generated.
A voltage of 3.3 volts is also produced by the power button, and by pressing the power button, the voltage is momentarily reduced to zero.
Now the rest of the voltages are generated in order.
Now check your motherboard and see what stage it is going to.
If it is in standby mode and it does not turn on by pressing the power button and the power button is healthy, you must first program the BIOS and then check the crystal 32.768 and then check the connection between IO and PCH.