The Odoo Studio module will help you to add smart buttons to any model you want. You can follow the below steps to add a smart button easily.

After enabling the studio module, you can navigate to the place where you going to add the smart button, and there will be a ‘+’ icon for adding the smart button, as shown below:

Click on the ‘+’ icon to see the options for a smart button. You can select the label, icon, and related field for the smart button.

Here, we can label the smart button as ‘Lines,’ add an icon, and select the sale order line as the related field.

After filling in these details, you will be able to see your smart button as given below:

If the developer mode is activated, you can see the details of your smart button while pointing the mouse over it.

Close the studio, and you can see your smart button on the view. The number inside the smart button indicates the number of related fields to the model.

Here, the number is 3, which means there are a total of 3 order lines.