In Settings > Business: Website set Website SEO Name (used as the site name in titles, the sitemap/manifest and structured data) and Website Description (default meta description). Per page or blog post, override them with the SEO Title and SEO Description fields in that item's Settings > SEO tab, and upload a Social image there for a dedicated share-preview picture (falls back to the page's regular featured image if none is set). Google Analytics, Google Tag Manager and the Facebook Pixel ID all live under Settings > Marketing: Analytics.