Ummm… no, you pick a time zone during install, that’s it. You might need to restart some services if you change your time zone (wouldn’t know, never had to change it).

That being said, it doesn’t come with an NTP client/server by default (as is with Ubuntu and other “everything works out of the box” distros), you have to install one manually. Once installed, the service is inactive, you have to make it active by symlinking a folder from one location to another (this is all explained on Void’s site, it doesn’t use systemd, it uses runit as it’s init/service manager). Restarting services is pretty easy (as is with systemd) sv restart name_of_service, that’s it.

I don’t think snap is available in the default repo (maybe in the non-free one, haven’t checked), but it does have flatpak in the default repo. Either way, couldn’t really help you regarding anything snap/flatpak related, I don’t use them. Everyting I need is in xbps-src, so I just compile from source (or repack, in case of non-free packages, like AnyDesk).