Hi and welcome. I'm Ansh and today, I will be trying my best to solve your issue.
Is it a laptop or desktop?
Please shut down the laptop
Remove the battery please
Press and hold the power button for 20 seconds
Connect the laptop to mains and push the power button once, without battery
Let me know if it starts
Glad to help :)
After the laptop starts, please shut it down properly and remove it from mains and reconnect the battery. Thank you