sleep function in a batch script

You can also use timeout.

Here is an example:

@echo off
echo Hi
timeout /t 1 /nobreak > nul

• /t is not mandatory

• 1 is the amount of second(s) to wait

• /nobreak ensures the user can't skip the wait

• > nul redirects output to nothing, so you don't see anything

SLEEP command may not be supported by your Windows version. Try this:

:a
START C:\Users\Mukul\Desktop\xyz.exe
TIMEOUT 14400
taskkill /F /IM xyz.exe
TIMEOUT 3600
goto :a

First off: Bash and Batch are very different languages.
Now, the answer.
I prefer the ping command over the sleep command, for it's easy switching between seconds and milliseconds:

ping -n 11 127.0.0.1>nul

That command pauses for 10 seconds then resumes.
Or:

ping 1.1.1.1 -n 1 -w 10001 >nul

Which also pauses for 10 seconds, but in milliseconds.

Either can be adapted into:

:a
start C:\Users\Mukul\Desktop\xyz.exe
ping -n 14401 127.0.0.1>nul
taskkill /F /IM xyz.exe
ping -n 3601 127.0.0.1>nul
goto a

DISCLAIMER: I have NOT tried the final piece of code (because I don't have 4 extra hours to do something).