How are sellers get the right photos for product

I am just a noob seller, trying to list smartphone case on Amazon. I have got some generic cases from local and i am trying to take photos for Amazon. The photos i take from myself doesn’t match the quality of the existing other sellers photos! I tried so many ways, but i am not able to understand whether the product images are real pictures or just rendered images.

I am just a noob seller and don’t have that much of a big budget to hire 3D designer or professional photographer. And if i upload photos i taken, i just afraid that no one would buy them because they doesn’t look as professional as others does.

I assume there are so many sellers here in this community. Suggestions and ideas are most welcomed.