1. In Shopify admin, go to Online Store → Themes.
  2. Find the Compose theme and select Customize.
  3. Open the page template you want to edit using the selector at the top.
  4. Select Add section, choose a section, and add your content.
  5. Drag sections and blocks in the left sidebar to reorder them.
  6. Check the desktop and mobile previews, then select Save.
Some sections belong to a specific template—such as Product, Cart, or Customer login—and are already present when you open that template. These sections may not appear in the Add section list.