How do you play Dungeons & Dragons?

With a calendar: when2meet.com.

I heard it had a really bad reputation, so I don’t recommend anyone playing it.

Dungeons & Dragons is a role-playing game, so you play the role of a character in a game world controlled by the GM (the Game Master, or in D&D they’re also specifically called the DM or Dungeon Master). The GM is the person who describes the world and what all the characters in it are doing, except the players control their own characters. The goal of the game is for the players to complete the challenges created for them by the GM, and of course for everyone to have fun while they do it.

Each character has a set of particular abilities that you choose for them out of the options in the rulebook. Dungeons & Dragons is a medieval fantasy game so the options are stuff like Wizards and Paladins (Knights) and Druids and stuff like that. The most basic choices for your character are their race, background, and class: so you could choose to be, for example, a Human Farmer Fighter (a class that uses weapons) or an Elf Scholar Wizard or a Gnome Criminal Rogue (Thief), out of the many, many possible options. You also have stats: Strength, Dexterity, Constitution, Intelligence, Wisdom, and Charisma.

Whenever you do something important, you will most likely have to roll dice. The most common die to roll is a d20 (a 20-sided die). Rolling high is good and rolling low is bad, usually: if you roll high enough, you succeed at what you’re trying to do, and if you don’t, you fail (which doesn’t mean you lose the game or anything, just that you fail at that one particular thing). Depending on your character’s stats and abilities, you might have a bonus or a penalty to the roll, which is why you have to choose your character’s abilities and stats based on what you want that character to do. For example, if you want to play a character that uses a sword, playing a Fighter and putting a high number in your Strength score will give you bonuses to using swords, while playing a Wizard wouldn’t.

The game is designed so that the GM creates a story, but the exact outcome of the story will depend on what the players decide to do with their characters and some amount of random chance with how the rolls go. The most common stories in D&D are usually along the lines where characters play adventuring heroes (more or less) who go around slaying fantasy monsters and gathering treasure, but you can play a game that’s about absolutely anything, really.

Does that all make sense?

One person is the “dungeon master”. They are sort of like a referee. They typically make the initial pitch of the game to the other players. That’s something like “I want to do a game about defending a town from zombies” or “wouldn’t it be cool to be like bank robbers in a fantasy world?”

The group then comes up with characters they want to play. DND has rules for what sort of powers and abilities characters have. This is mostly captured by “character class” (fighter, wizard, paladin, etc). You might say "I want to hit things with a sword so I’ll be a fighter " or “I want to learn magic so I’ll play a wizard.”

Unlike playing a board game, you also come up with some story bits for your character. So you might play a wizard who’s fresh from wizard school and turned to bank robbing to pay off student debt. Or an old wizard that needs money to pay for expensive magical healing. It is pretty wide open, though not totally open. Some new players will try to do like “my dad is the king and my mom is an angel and I can fly and…”, and forget to sync their story with the rules parts. And ideally whatever story idea you have hooks into the pitch.

Once you’ve done all that, you get together as a group (virtually or in person). The DM (dungeon master) will describe the initial scene. “You’re just kicked open the door to the bank office. Your tip said it was going to be empty, but two elves are sitting behind a large desk. They jump up, startled and surprised. The room is ostentatious. Marble floors. Stained glass floor to ceiling windows. Magical lights hanging from the fifteen foot ceiling.” The dm will probably ask what you do.

Note that the dm generally describes the scene and characters that aren’t being played by one of the players. The players in DND generally only control their specific characters. In dnd a player could not be like “the elf runs away in a panic!” or “suddenly all the lights go out!”. Only the dm can declare what the world and its non-player inhabitants do. The players control their characters only. (non DND RPGs may differ on this point)

A player may ask questions. “are the elves armed?”

The dm may answer. “you don’t see any obvious weapons”.

The dm may ask you to roll dice to determine if you succeed at something, notice something, or know something. “Roll perception for me to see if you notice anything else.”

When you check if you succeed at something like that in DND you roll a 20 sided die, and often add something to the result based on your character. A smart character has a bonus for knowing stuff, and a strong one to physical challenges, as examples.

“That’s a 17 on perception? You notice a magical wand on the desk, half covered by papers, and the elf glanced at it.”

Players may declare they’re doing something. “I want to lunge for it before the elf picks it up!”

The dm may call for a roll to see how that goes, and narrate the outcome.

This process of the dm describing the scene and the players asking questions / taking actions continues. If a fight breaks out, combat in DND has a lot of specific rules for determining if attacks hit or miss, if someone is taken out of the fight, and so on.

Usually people play for a few hours at a time, and pick up the story the next time they play. So the first session might be trying to rob the bank vault and getting in a fight with the staff, the second might be cracking the vault and escaping, the third might be a showdown with the head of security with a horseback chase. Much of this will be made up by the DM. They may not have expected the players to steal horses and ride into the desert, but if that’s what the players do they will make something up. This is the big appeal of RPGs over videogames. You can do anything the group thinks is cool. It doesn’t need to be scripted ahead of time.

Much of this as I’ve described it applies to non-dnd RPGs, too. DND has a lot of very specific things about it I’ve kind of glossed over. It has very idiosyncratic combat and magic systems, for example. You’ll hear people talk about “roll for initiative”, “saving throw”, “critical hit” and more. Those are details for dnd’s rules.

Honestly DND is kind of a bad first rpg. It’s very popular but it’s also extremely janky, and only does adventuring day fantasy at all well. Games about political intrigue or social conflict don’t do well in DND specifically because it doesn’t really have detailed rules for them. It’s also pretty harsh on allowing players to be creative compared to other games.

This is very long but I hope it was helpful.

Just a small addition to the other comments, who kinda wrote already everything that’s important - for your first play try to look for an experienced dungeon master (that might be a good idea independent of the actual meaning of the phrase), it might kill the mood if everyone is trying to figure out the rules at the same time