A new player joins your Discord, gets the Player role and makes a character. What the form asks, how many characters they can keep and whether a GM checks each one first are up to you, and nearly all of it is in Settings → Character Settings. The player's side is in Joining as a Player, which is the link to paste into your Discord.
Not here, and that's on purpose. The site keeps what a West Marches needs when every session has a different group: level, experience, currencies, where every bit of it came from, and whether the character is still alive. The sheet stays in D&D Beyond, Foundry, a Google Doc or wherever the player likes, and they paste the link into Character Sheet URL.
Leave that field required if your GMs read the sheet before they approve a character. If some of your players still use paper, switch on "Make character sheets optional".
A D&D Beyond link does a bit more. If the sheet is public, the character page shows its ability scores, Armor Class and hit points, and GMs get those and more on the DM screen during an adventure. The D&D 5e guide has the details.
Character Creation Guidelines sits at the top of the character form every time a player creates or edits one. Finding the house rules is one of the hardest parts of joining a new West Marches, so put the allowed books, starting level and banned options here. The site doesn't check any of it. GMs do.
Attributes are your own fields on the character form, under Character Attributes. Keep the list short. The full sheet is somewhere else already, so only add what a GM wants to see at a glance, like class or faction.
An attribute is free text, one option from a list you write, or several, and only the option types can be filters. Show on adventure signup puts the value in an adventure's list of players, so the GM can see who is bringing what. Filterable adds a filter on the Characters page, and it's a Patreon feature.
Deleting an attribute deletes every character's value for it.
Retired, deceased and deleted characters don't count toward either limit. Players can't retire their own or mark them deceased, so they ask a GM. A deleted character can be restored by the community owner and anyone who can approve characters.
A West Marches is meant to be deadly, and a player whose favorite character just died should still be able to sign up for the next adventure. The default of three leaves room for that.
New characters wait for a GM unless you switch on "Automatically approve all new characters". In a group of friends, switch it on. In an open community full of strangers, leave it off and look at each character before it plays.
Until then the character can't sign up for adventures. The bot posts it in your Characters channel, questions go under that post, and a GM clicks Approve Character when it's ready. Your GM and Admin roles have the "Can approve/delete characters" permission from the start (Settings → Roles & Permissions).
Moving a campaign that started somewhere else? Then the characters aren't level 1 any more. Settings → Experience Ladder has a switch that lets players type in their starting experience, and each currency under Settings → Currencies has one too. Approval locks those numbers in.
Character Settings also has "Allow players to adjust experience themselves" and the same for currencies, which give players the Give Rewards button on their own characters. Leave them off unless you want players to handle things like selling loot themselves.
Stat Rolling rolls ability scores on the character form with your Dice Formula, and the player picks one of the sets. No rerolling until they make a character or the sets expire.
Hit Point Rolls give each level from 2 up a slot where the player rolls their hit die or takes the average. They follow D&D's rules and need the Heroic tier. Both post in the Stat & HP Rolls channel once you pick one in Discord Channels. The D&D 5e guide goes through both.
Export Characters, at the bottom of Character Settings, downloads every character as a CSV. Export Community, in Settings → Advanced, adds their rewards, inventories and adventures, plus the wiki.