Click Settings in the sidebar (requires the view_settings permission). It is a grid of cards: Email Sending, Business Branding, Support Notifications, Message Shortcuts, Shortcodes, Files, plus one card per configuration section (Contacts, Templates Import, Stripe, Telephony, Calls Settings, Header Navigation, Business Info, Representative Info, Business Address, Onboarding, HubSpot, Calendly, Monday, Salesforce, Modules and more). Click Edit or Manage on a card to open it.