One of the limitations when using the Schema Builder for creating fields is:
C . Cannot add fields to page layouts. While Schema Builder allows for easy visualization and creation of fields and objects, it does not support placing these fields onto specific page layouts directly from the Schema Builder interface.
To place fields on page layouts, you need to:
Navigate to Setup → Object Manager → select your object.
Click on Page Layouts, choose the appropriate layout, and manually add the newly created fields.
This step is necessary to ensure fields are visible and properly arranged on user interfaces.
For more details, Salesforce's Schema Builder documentation outlines its capabilities and limitations.