Writing your own campaign in Dungeons and Dragons is an incredibly rewarding experience, but it can also be very difficult. Luckily, Wizards of The West Coast regularly publishes their own adventures, which can take a lot of the load off the shoulders of DMs that don't have a ton of time or would rather just tell a pre-written story.
These still take time to prepare, and it's always worth reading a whole adventure before running it, but it's still easier than designing an entire world and narrative. Of course, every campaign will have some type of roadblock that a Dungeon Master will have to overcome, but at the end of the day, it'll make them better for it.
5 Storm King's Thunder
Let's be clear, Storm King's Thunder takes quite a bit of prep work. It's very open-ended, which can be a curse and a blessing as a DM. There are plenty of Dungeon Master tips to be doled out over the best way to run Storm King's Thunder for your group of Dungeons and Dragons players, but the best route to go is to download the Storm King's Thunder guide on DM's Guild. It'll make running the entire thing a lot easier, though SKT really isn't bad for new DMs. What's great about it is that it still allows the DM to run a heap of side adventures, making it the best of both worlds for DMs that still want some creative freedom. Of course, those that aren't comfortable with how open the campaign is may want to find a different option.
4 Out of The Abyss
While it can be chaotic at times, Out of The Abyss is very easy to set in motion, something many DMs have trouble with initially. Plus, the Underdark is actually a pretty interesting place in the D&D mythos, and there are a ton of things a DM can do to put their own unique flair on the various locations players will have to visit. That being said, it may be worth bending the rules a bit for player characters that don't have Darkvision as a feat, otherwise, they'll spend their entire time stumbling around the Underdark, which is never any fun.
3 Defiance In Phlan
If one thing is for certain, Defiance in Phlan will help the DM, and players, nail down the basics of D&D. The adventure is really five bite-size adventures put together in one package, making them incredibly easy to manage. That being said, Defiance In Phlan isn't long. It's primarily intended as a way to introduce players to the Adventurer's League, and most parties will be able to clear it in one or two sessions - each of the five missions taking roughly an hour to complete for those that remain on track. Still, it's an easy campaign to run, though it's intended for level 1 characters.
2 Tales From The Yawning Portal
Tales From The Yawning Portal is an interesting beast. It's a collection of adventures from previous editions updated for Fifth Edition, some dating all the way back to the '70s. And while this means that there are decades worth of notes on the best way to run some of the adventures, it is worth noting that some of the adventures will be deadly, and it may be worth players having a backup character or two, just in case. Like Defiance in Phlan, the modularity is a good thing, though it will be quite a bit more intense for the most part.
1 Lost Mines of Phandelver
There's a reason that Lost Mines of Phandelver comes with most of the basic D&D kits out there. Not only is it a great way to introduce new players to the game, but it's also a stellar option for first-time DMs looking to learn the ropes. By the end, most Dungeon Masters will be prepared to run meatier campaigns, having gained a better understanding of what it means to be a Dungeon Master in the first place. Those looking into D&D for the first time but unsure of where to start should absolutely consider Lost Mines of Phandelver as a go-to.
It's important to remember that these campaigns can be modified in any way the DM sees fit. If there's a particular aspect of a campaign that's causing frustration, it's perfectly fine to cut it. Also, remember that every player is different, and it's important to find the right balance combat, roleplaying, and exploration to please your entire table, which comes down to picking the right campaign. Even after a DM has chosen, or created, a campaign, there will still be a few thing Dungeons and Dragons players need to get started, so be sure to take inventory of everything before kicking off an adventure.