Press Build it in your server and the bot applies the design live, item by item, with a progress bar and a running list of what landed. A snapshot of your server is saved just before anything changes.
Deletions are always opt-in
Building never removes anything by default. If the design proposes deletions, they appear as unchecked boxes with the note Deletions are off by default. Check only what you want removed. A second list, In the server but NOT in your design, offers existing items you could remove so a rebuild comes out clean, and Start fresh checks them all at once. Anything you check requires ticking a confirmation that the items and their messages are deleted permanently.
Items marked Kept for your enabled features are protected: they belong to features that are switched on (like open ticket channels) and deleting them would break the feature. To remove them, turn the feature off on the Services page first.
Leaving things out
Open Review and build and every planned change has its own checkbox. Uncheck a row and that one change is left out of the build; everything else still runs.
New-member onboarding
When a design includes onboarding, an opt-in checkbox offers to set it up: it turns on Discord's Community mode, adds a rules and a moderator-updates channel and configures the welcome screen and starter questions. This needs the bot to have Administrator. One step stays yours: the rules agreement gate is switched on by you in Discord's Server Settings, since bots aren't allowed to do it.
If some items fail
A build never stops halfway because one item fails; it finishes everything it can and then shows a Build report: what didn't land and why. The most common cause is a locked channel or a role above the bot. Drag the bot's role to the top of the role list or grant it access to the locked channel, then press Retry the failed items. Building again is always safe: anything that already exists is skipped, never duplicated.