Hi RuchiAgarwal15,
I am Dave, I will help you with this.
That indicates your laptop is trying to boot from a network drive, not the internal drive.
1
What are the beep codes you hear when you start the laptop, is there a pattern to the beep codes?
2
Boot your laptop into BIOS (F2 on the Dell logo screen)
Find the option to restore BIOS defaults on the Save tab, apply that, save those settings and restart your laptop, does it boot into Windows?