Hi, ayushgurung2.
I'm Jen, a Windows 10 user just like you. I'm not working for Microsoft but I'd be happy to help you figure this out.
I'm sorry to learn that you're having trouble signing in to your Windows 10 PC. There are ways to reset/gain access to your account, however, it will depend on your account type. I shared a link below that may help you and I suggest following the method suitable for your account type.
https://www.techadvisor.com/how-to/windows/how-...
*****Note: This is a non-Microsoft website that would provide accurate and safe information. Watch out for ads on the site which are frequently classified as a PUP (Potentially Unwanted Products). There is no need to buy paid products to fix your computers as they do more harm than good sometimes.*****
I hope this helps. Feel free to share how it went.
Kind regards,
JC