If you suspect that the battery is dead and the charger is broken, you can only use your own multimeter to measure it, or try using other appliances or light bulbs.
3. If you see words appear on the screen, but you can't boot it, it may be that the system is damaged.
4. Otherwise, there may be something wrong with the hardware. Disassemble the back cover, insert the memory module and try the hard disk. If it doesn't work, it can only be repaired.