Carrier Calculated Shipping must be enabled for your store to access and display Sendle shipping rates.
To be eligible, your shopify plan must meet both of the following requirements:
1. It is on the Shopify plan or higher. (Not Basic Plan)
2. Your Shopify plan is changed to paid annually.
Once both of the above is true, please contact shopify support who will enable it immediately when requested.
After that go to the following link and install the app
https://apps.shopify.com/sendleshipping
After installing it go the admin-> app -> sendle
- After login to the admin go to Left-menu -> Apps -> then select Sendle

2. Then add General Settings like Title, Description, Sendle ID, API Key and Sandbox/live Mode like the following screenshot.

3. Then add Order Sync Settings like the following screenshot
