Check Last Reboot History
Mostly Linux/Unix systems provide the last command, which provides us the history of last logins and system reboots. These entries are keeps in the lastlog file. Run the last reboot command from the terminal, and you will get the details of the last reboots. The above output shows that the system was last rebooted on Nov 28 at 06:14 AM.
Check System Uptime
Additionally, you can also use the uptime command to find the system uptime from last booted. Just open the terminal on your system and type uptime and hit enter. as per above output, the system is running from 65 days, 5 hours and 42 minutes.