Apply Configuration Changes/Reload Asterisk

If I add extensions to the Database, or Delete them. and then add or delete voicemail boxes from the voicemail.conf file, what cli commands can I run to reload these settings on the server?

from an ssh session:
amportal restart

From the Asterisk CLI (under the tools tab in freepbx)
restart now

if you are just adding lines into the sql database it is very likely you are not adding all the information you need to properly add those extensions. I think the answer you are looking for is retrieve_conf followed by reload at the CLI, but if you are trying to do what it sounds like you asked about, it’s likely you will have a corrupted system.