Need help about Item Import Image With Webhook Link

I Imported my items and linked image from my S3 , It showing images all looks fines ,
but when same item i want to publish to web i get error about webhook image link its not readable , now what i did i removed webhook image link which i used while importing and again attached manually same webhook image but but this time i did by selecting public …
after attaching same webhook image public this same item able to publish as web item ,
Now Question is

  1. DO i need to need to import my items all as public if i am not wrong this is not secure
  2. If not when how i can set only webhook link as public so that all my items which imported as bulk i can also publick as webitems too ,
    Looking forward from seniors Input