1)Extension setup:
In Shopify admin, click Sales Channel => Online Store => Customization => App Embeds => Enable Discount Price
2) Block Setup:
In Shopify admin, click Sales Channel => Online Store => Customization => In Home Page drop down select Products => Click on Default Product => In Product information click on Add block => In APPS click on Quantity Selector Widget => Drag and drop Custom Price Grid below Price (in Product information)
3) Check Settings if App is Enabled (ON)
4) If any other Price related App is installed, it may conflict with our App. So you can disable other pricing related Apps in order to view the Discount Widget Table on the product page.