I recommend you use what you are most comfortable with. There will be few differences between Debian and Ubuntu in a server context.
Neither is “easier”, though maybe Ubuntu has a bigger community of users, but docs for one apply to the other almost always, since Ubuntu is based closely on Debian. Though, lately, Ubuntu is moving to snap packages for more of the system, which is theoretically better by some metrics, but practically it is much, much, worse. snap is becoming a reason I avoid Ubuntu.