Dell Vostro 15 3568 doesn't start up correctly

I got this laptop in refurbished condition year ago, and it worked fine before, until I got an issue with this laptop.

When I shutdown Windows 11 without any pending updates, and turn the laptop back on, the laptop doesn't want to POST (the fan spins up, but the display remains off). I tried to remove the (poor) battery, unplug the AC adapter, plug it back in, and turn it on, but I only got Dell logo at startup and nothing else (I couldn't go into BIOS setup, boot menu, or even booting Windows).

I also tried to remove one of the RAM module, remove the CMOS battery, put it back in, and turn on the laptop again. When turning on this laptop, the fan spinning faster, and few seconds later the indicator lamp blink continuously. I turned on the laptop, and got same issue, and when I turn on the laptop for the second time after removing the CMOS battery, the laptop turns on, but the screen didn't comes up until around 5-10 seconds the screen finally came up, but this time, it didn't show a Dell logo, but rather, a black screen with blinking cursor at the top corner. I thought this issue is caused by corrupted BIOS, but I couldn't restore the BIOS by plugging in FAT32-formatted USB drive with BIOS_IMG.rcv inside and hold Ctrl+Esc before powering on the laptop.

I know Windows 11 is not supported on this laptop, but I use it all the time since I got this laptop, and the Windows 11 install is still working properly