Put lv_conf.h inside my arduino Sketch Folder

How-to
2

Have you tried as below?

#define LV_CONF_INCLUDE_SIMPLE
#include "lv_conf.h" // <-- path to your lv_conf.h

#include <lvgl.h>
#include "src/ui/ui.h"
#include "src/ui/ui_helpers.h"