Normally, Joomla will notify you when an update is available for JoomProject in your website backend. If your site or server configuration does not support automated extension updates, you can always install the update manually through the Joomla extension Manager in:
Joomla Backend -> Extensions -> Extensions Manager
Also don't forget to copy your Download ID and paste it in JoomProject Dashboard
If you want to update from Joomla 3 to Joomla 4 read this article