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Thank you @teukudianaulia. You can use whatever you want, however, you could get caught for copyright infringement. This is super rare with small pages, however, if you start reaching a lot of people it can become an issue. I suggest looking into unsplash.com or do a quick google search (no pun intended) for "best sites for free stock photos". There you will find all you need. Hope that helps!

thank you, that'll help @axios

no prob!

You can use any picture from Google, but you have to mention the links of the images in your post. Like: Source Images:1, 2 etc.

thanks for the information @fathin-shihab