Select the wp-content on Custom Fields —> Field Groups
Click on Add New Button Then after Add New Field Group Name and Add Fields like Fields Label, Fields Name, Fields Type.
Title:-
Each Field Group Requires a Title. Title is shown in the Metabox Handle on The Edit Screen to use
Relevant Titles Such as “Home Page”.
Fields:-
Here you can create and manage a variety of custom fields. Clicking the “Add Field” button will create a new field and add it to the bottom of the list (you can reorder your fields by dragging the order number as a handle). Adding a field will look like this: