After creating a page in LayoutHub, the page will be synced with Shopify. So you can change page title, description and page handle in Shopify or in the app.
In Shopify: Simply go to Online store => Pages => Edit page => Edit website SEO
In LayoutHub app: From the app dashboard, go to edit page:
Click on the "Publish page" button:
Here you can see the Page title, Page handle and Description options. Simply update them and click on Publish now button.