Use the invite link, add the bot to the right server, and give the Quotable role access anywhere you want message-based quoting to work.
Reply-based quoting and message ID saves work best when most channels inherit access from the category.
If a staff or private channel blocks the bot, slash commands may still appear there but quote actions can fail.
If your server uses Wick or similar tools, make sure Quotable is allowed to stay in the server and post where needed.