Permissions in Reaction are quite basic and are controlled by Discords built-in slash command permission system. You simply grant or deny certain roles permission to use the /config command. There are two simple commands to control access to the config command, and each only takes a singular role argument.
The user who first adds the bot will be the only one with permission to use the /config command. They will need to grant permission to roles that should be allowed to configure the bot.