how to add field programmatically in Drupal 7 with dynamic content value?
I'm not sure what you are trying to do. But if you are trying to add a new field programmatically, below is a code snippet that can get you started.

    $myField_name = "my_new_field_name";
    if(!field_info_field($myField_name)) // check if the field already exists.
    {
        $field = array(
            'field_name'    =&gt; $myField_name,
            'type'          =&gt; 'image',
        );
        field_create_field($field);

        $field_instance = array(
            'field_name'    =&gt; $myField_name,
            'entity_type'   =&gt; 'node',
            'bundle'        =&gt; 'CONTENT_TYPE_NAME',
            'label'         =&gt; t('Select an image'),
            'description'   =&gt; t(''),
            'widget'        =&gt; array(
                'type'      =&gt; 'image_image',
                'weight'    =&gt; 10,
            ),
            'formatter'     =&gt; array(
                'label'     =&gt; t('label'),
                'format'    =&gt; 'image'
            ),
            'settings'      =&gt; array(
                'file_directory'        =&gt; 'photos', // save inside "public://photos"
                'max_filesize'          =&gt; '4M',
                'preview_image_style'   =&gt; 'thumbnail',
                'title_field'           =&gt; TRUE,
                'alt_field'             =&gt; FALSE,
            )
        );
        field_create_instance($field_instance);
        drupal_set_message("Field created successfully!");
    }


Hope that works

Muhammad.