Hi tharun,
Thanks for reaching out to Microsoft Q&A.
Try hard reboot your PC try to boot into recovery mode and from there access system repair/safe mode. If this doesn't work or you couldn't come up to this stage, the only way is to reinstall windows using bootable USB. Sorry but there aren't much options from microsoft or any other experts from such state of your PC.
Please Upvote and Accept as answer if the reply was helpful.