Use TaskMgr Perfomance Tab
net stats srv
Use “Systeminfo” and find….
C:\Users\User>systeminfo | find /i "System Boot"
System Boot Time:          3/30/2022, 7:34:10 AM
For Unix
uptime -p
Reference:
   https://www.groovypost.com/?s=Find+How+Long+Your+Windows+Computer+Has+Been+Up+and+Running
   https://www.technipages.com/windows-10-how-to-see-system-uptime